MCB 3413 Final Exam

What does the Gal4/UAS system do?

- binary system used for tissue specific expression - an expression system used to target gene inactivation in a tissue specific manner - used to drive the expression of a hair pin RNA

How is RNAi? What are its native functions? How does it work?

- hairpin RNA for each gene, a biological process in which RNA molecules - RNAi is able to exert an organism wide effect in both plants and worms, suggesting dsDNA or silencing effect is somehow passed between cells in these organisms - work depends on the organism

Transposable elements account for a large percentage (~50%) of the DNA sequences in the human genome. What are the most abundant 2 types of transposable elements in humans? What is the relationship between these transposons?

- long interspersed nuclear elements (LINES) - short interspersed nuclear elements (SINES) - LINES are autonomous while SINES are non-autonomous (need LINES to make SINES)

What are the direct consequences of meiotic recombination with an inversion?

- may produce acentric fragments (no centromere) - disruption of recombination in heterozygosity by both reducing crossing-over with the inverted regions and increasing it elsewhere

What are the similarities and differences of the life cycles between retrotransposons and retroviruses?

- transposition of a retrotransposon --> An RNA transcript from the retrotransposon undergoes reverse transcription into DNA, by a reverse transcriptase encoded by the retrotransposon. The DNA copy is inserted at a new location in the genome

Among the following molecules; gene-specific sequence? Universal primers? Molecular bar code? Kan-R? 1) which is/are important in subsequent studies to identify a mutation, such as uracil defect mutants? 2) Which is/are important in subsequent studies to identify a mutation, such as uracil defect mutants? 3) which molecule is used to identify a uracil defect mutant in a microarray assay?

1) Kan-R and gene specific sequences 2) universal primers and molecular bar code 3) molecular barcode

Which of the follow sequences includes a clear 8 base pair palindrome? A) 5'-CCGATCGATCCC-3' B) 5'-TGGGGTTTTG-3' C) 5'-GGGGAAAA-3' D) 5'-GATCCTAG-3' E) 5'-AACCAACCAA-3'

A) 5'-CCGATCGATCCC-3'

Among the following products that are derived from a CRISPR-cas9 experiment, which is generated without a template? A) a small deletion B) a defined deletion C) a gene editing product D) all of the above E) none of the above

A) a small deletion

When the FLPase is present, a DNA molecule containing two FRT sites oriented in the same direction A) can generate a circular molecules and a linear molecule B) can generate two circular molecules C) two linear molecules D) all of the above E) none of the above

A) can generate a circular molecules and a linear molecule

A plant is homozygous for a point mutation in gene "B". This plant produces wild-type "B" protein in wild-type amounts, but a more detailed analysis reveals that the "B" mRNA produced by this plant is two nucleotides shorter than wild type. The mutation is most likely a two base pairs deletion: A) downstream of the STOP codon, in the last exon of gene "B" B) in an intron of gene "B" away from the splice sites C) in the open reading frame of gene "B" D) that removed a splice site of gene "B" E) within the promoter of gene "B"

A) downstream of the STOP codon, in the last exon of gene "B"

Which of the following statement is NOT true? The PhiC31 integrase system A) is one of the site-specific recombination systems B) has two target sites, attB and attP C) provided site-specific integration D) is extremely efficient E) provides opportunities to place transgenes at a desired location

A) is one of the site-specific recombination systems

In a complementation test for a recessive phenotype, a genotype carrying both of the mutant-a allele and the mutant-b allele failed to complement. This is a case where __________. A) the mutant-a allele is not related to the mutant-b allele B) the mutant-a allele and the mutant-b allele are allelic to each other C) the genotype of the double heterozygote, a/b, has a wild-type phenotype D) all of the above E) none of the above

A) the mutant-a allele is not related to the mutant-b allele - complementation: the production of a wild-type phenotype when 2 recessive mutant alleles are brought together in the same cell

What does it mean when we say Drosophila RNAi cell autonomous? Explain the necessity to downregulate drosophila gene expression by expressing an RNAi molecule in the target cell.

Autonomous is when an element can be transposed through the action of its own transposase enzyme gene expression is downregulated so that less protein is produced

In the eukaryotic GAL system, the physiologically regulated step is: A) DNA-binding by the transcriptional regulator B) Activity of the activation-domain of the transcriptional regulator C) feed-back inhibition by the end-product of the pathway D) important of the inducer molecule E) none of the above

B) Activity of the activation-domain of the transcriptional regulator

Among the following mutation, which is dominant? A) Amorphic allele (null) B) Neomorphic allele (gain of function) C) hypomorphic allele (leaky) D) all of the above E) none of the above

B) Neomorphic allele (gain of function)

Chimerism and mosaicism are used to describe two related genetic phenomena. Chimera is a single organism composed of cells from. A) a single fertilized egg B) different zygotes C) both a single fertilized egg and different zygotes D) all of the above E) none of the above

B) different zygotes

Targeted gene knockout is used in reverse genetics, it A) does not need to know the genomic sequence B) involves a double crossover C) always relies on the known phenotype D) was developed originally in Drosophila E) all of the above

B) involves a double crossover

Recombinant DNA techniques typically require the action of A) DNA polymerase and phosphatase B) restriction enzymes and DNA ligase C) RNA polymerase and RNA primase D) reverse transcriptase E) DNA helicase

B) restriction enzymes and DNA ligase

When seeking to identify the gene that is responsible for a particular cellular characteristic, scientists will generate cells carrying a recessive mutation that perturbs the characteristic of interest and then try to identify or "clone" the wild-type copy of that gene through functional complementation. This type of complementation could be described as: A) intensification of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest B) reversal (rescue) of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest C) identification of two different genes that both regulate the same cellular trait D) a biochemical phenomenon where an enzymatic process is eliminated by plasmid DNA expressing a gene of interest E) mutation of a gene of interest to complement an opposing biochemical pathway

B) reversal (rescue) of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest

Genome editing technique using CRISPR-cas9 utilizes several well-chracterized natural biochemical reactions. What is NOT part of these reactions? A) double stranded break at the target sequence B) synthesis of a guide RNA C) DNA repair using the non-homologous end joining pathway D) all of the above E) none of the above

B) synthesis of a guide RNA

A highschool student is in the process of designing a guide RNA for bacterial genome editing experiment by using the CRISPR-cas9 system. Before ordering the guide RNA, the student needs to know A) the target sequence B) the target sequence and PAM on the strand non-complementary to the guide RNA C) the target sequence and PAM on the strand complementary to the guide RNA D) all of the above E) none of the above

B) the target sequence and PAM on the strand non-complementary to the guide RNA

Homologous recombination in yeast facilitates: A) the segregation of genes during meiosis B) the targeted replacement of a gene in a living yeast cell C) the amplification of homologous yeast genes D) the independent assortment of separate gene alleles E) the expression of similar gene sequences via one promoter

B) the targeted replacement of a gene in a living yeast cell

Transposable elements that are comprised of DNA transposons are known as: A. class 1 elements B. class 2 elements C. class 3 elements D. alpha elements E. D elements

B. class 2 elements

When seeking to identify the gene that is responsible for a particular cellular characteristic, scientists will generate cells carrying a recessive mutation that perturbs the characteristic of interest and then try to identify or "clone" the wild-type copy of that gene through functional complementation. This type of complementation could be described as A. intensification of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest B. reversal (rescue) of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest C. identification of two different genes that both regulate the same cellular trait D. a biochemical phenomenon where an enzymatic process is eliminated by plasmid DNA expressing a gene of interest E. mutation of a gene of interest to complement an opposing biochemical pathway

B. reversal (rescue) of the recessive mutant trait via transferred plasmid DNA carrying the gene of interest

Homologous recombination in yeast facilitates A. the segregation of genes during meiosis B. the targeted replacement of a gene in a living yeast cell C. the amplification of homologous yeast gene D. the independent assortment of separate gene alleles E. the expression of similar gene sequences via one promoter

B. the targeted replacement of a gene in a living yeast cell

The essential components of the CRISPR-cas9 system include A) Cas9, a specific target sequence B) Cas9, a specific target sequence, a guide RNA C) Cas9, a guide RNA D) cas9, a guise RNA, crRNA E) cas9, a guide RNA, tracrRNA

C) Cas9, a guide RNA

In a therapeutically engineered dominant negative allele, it is __________ domain that is mutated, resulting in ____________ A) protein-protein interacting domain and destruction to the translational activities B) DNA-DNA binding domain and destruction to transcriptional activities C) DNA-protein binding domain and destruction to transcriptional activities D) all of the above E) none of the above

C) DNA-protein binding domain and destruction to transcriptional activities

Among the following products that are derived from a CRISPR-cas9 experiment, which is generated with a template? A) a small deletion B) a defined deletion C) a gene editing product D) all of the above E) none of the above

C) a gene editing product

To learn molecular function of a protein domain, __________ can be used A) a simple transposon insertion to disrupt the gene function B) constructing a GFP reporter gene C) a gene replacement to modify a genomic site corresponding to a protein domain D) all of the above E) none of the above

C) a gene replacement to modify a genomic site corresponding to a protein domain

When the FLPase is present, a DNA molecule containing two FRT sites oriented in the same direction A) can generate a duplication B) can generate more copies of the target sites C) can generate a deletion that retains a FRT site D) all of the above e) none of the above

C) can generate a deletion that retains a FRT site

TRiP is an RNAi project to establish a collection of Drosophila strains carrying UAS-RNAi transgenes. TRiP utilized 2 attP chromosomes sites to insert UAS-RNAi transgenes. What were two most significant factors in selecting the attP sites? A) highly inducible sites, and also high basal transcription B) highly inducible sites, but basal transciption is not important C) highly inducible sites, but basal transciption is low D) all of the above E) none of the above

C) highly inducible sites, but basal transciption is low

A wild-type chromosome can be represented as ABC[*]DEFGH, and from this a chromosomal aberration arises that can be repreented ABC[*]DEGFH, where [*] represents the centromere. This aberration is known as a: A) deletion B) duplication C) paracentric inversion D) pericentric inversion E) translocation

C) paracentric inversion - centromere is not w/in inverted seq - centromere is w/in inverted sequence i.e. ADEFGH [*]BC

The CRISPR-cas9 gene editing system has two major components. However, an additional sequence adjacent to the targeted site is important in designing a gene editing experiments. It is A) the gene encoding the cas9 enzyme B) the cas-9 cut sites C) the PAM trinucleotide D) all of the above E) none of the above

C) the PAM trinucleotide

In an early attempt to generate a genome-wide collection of Drosophila RNAi strains, it was found that ~45% of the strains carrying the UAS-RNAi transgenes failed to show expected lethal phenotypes, when a uniquitous driver, Act5C-Gal4 was used. This was likely caused by A) some of the UAS-RNAi transgenes were damaged during the experiment B) RNAi would not work on some of the genes C) the UAS-RNAi transgenes were inserted randomly via P-elements and subjected to PEV D) all of the above E) none of the above

C) the UAS-RNAi transgenes were inserted randomly via P-elements and subjected to PEV

The target specificity of the CRISPR-Cas9 system is provided by A) the cas9 enzyme B) the PAM site C) the guide RNA D) all of the above E) None of the above

C) the guide RNA

What percentage of the human genome is derived from transposable elements? A. less than 5% B. 25 % C. 50% D. 75% E. Nearly 100%

C. 50%

Which of the following scientists discovered the Ac-Ds transposable elements in maize? A. Marcus Rhoades B. Rollins Emerson C. Barbara McClintock D. George Beadle E. all of these scientists made the discovery

C. Barbara McClintock

DNA elements that prevent the spreading of heterochromatin into adjacent euchromatic regions are called: A. enhancer blocking elements B. euchromatin buffers C. barrier insulators D. barrier buffers E. barrier-blocking elements

C. barrier insulators

LINES differ from retrotransposons in that LINES: A. do not encode transposase B. do not encode reverse transcriptase C. do not contain LTRs D. do not transpose in a replicative manner E. do not contain the transposase gene

C. do not contain LTRs

Thymidine kinase is valuable in the targeting of mouse genes because A. it enhances the efficiency of gene replacement B. it suppresses expression of the target gene C. it allows researcher to enrich cells for those that have undergone homolgous recombination D. transgenic cells are resistance to gancyclovir E. transgenic cells are sensitive to gancylovir

C. it allows researcher to enrich cells for those that have undergone homolgous recombination

Eukaryotic retrotransposons such a Tyl and Copia are flanked by: A. direct repeats (DRs) B. inverted repeats (IRs) C. long terminal repeats (LTRs) D. long inverted repeats (LIRs) E. none of the above

C. long terminal repeats (LTRs)

The GAL4 enhancers are located ______ of the genes they regulate and are known as ______. A. downstream; downstream activation sequences (DAS) B. downstream; downstream enhancer sequences (DES) C. upstream; upstream activation sequences (UAS) D. upstream; upstream enhancer elements (UES) E. none of the above

C. upstream; upstream activation sequences (UAS)

Which of the following statements is NOT true? A) Yeast knockout is a targeted mutagenesis system B) Mouse knockout is a targeted mutagenesis system C) RNA i could be used to develop a targeted mutagenesis system D) P element insertional mutagenesis is a target mutagenesis system E) CRISPR-cas9 is targeted mutagenesis system

D) P element insertional mutagenesis is a target mutagenesis system

Which of the following statements is NOT true? A) targeted insertions are often used to generate mutations by disrupting genomic sequences B) targeted insertions are often used to generate mutations by replacing genomic sequences C) targeted insertions are often used to generate reporter genes to learn when and where genes are expressed D) Targeted insertions can be achieved by single crossover between homolgous DNA sequences E) targeted insertions can be performed by using site directed recombination

D) Targeted insertions can be achieved by single crossover between homolgous DNA sequences

Prior to CRISPR-cas9, gene replacement methods often rely on the generation of double strand break (DSB). These include A) P element excision induced DSB in Drosophila B) TC1 excision induced DSB in C. elegans C) Zinc finger nuclease induced DSB D) all of the Above E) none of the above

D) all of the Above

Both germline mutations and conditional mutations, such as those induced by RNAi, are important in learning the function of genes. Conditional mutations of RNAi could be used to study function of A) essential genes B) pleiotropic gene activities: early and later functions C) genes in redundant pathways or with functional redundancy D) all of the above E) none of the above

D) all of the above

DNA double-stranded breaks can be repaired via non-homologous end joining (NHEJ) and homologous recombination (HR). Among the following products that derived form a CRISPR-cas9 experiment, which is generated via HR? A) a gene replacement B) a targeted insertion C) a gene editing product D) all of the above E) none of the above

D) all of the above

In addition to yeast cells, Gal4 has been shown to activate transcription in A) insect cells B) mouse cells C) human cells D) all of the above E) none of the above

D) all of the above

Site specific recombination systems can be engineered to __________ A) produce chromosome insertions B) produce chromosome deletions C) produce recombination between chromosome and extra chromosomal DNA fragment D) all of the above E) none of the above

D) all of the above

The inverse PCR technique A) is based on A. Kornberg's in vitro DNA synthesis principle B) involves the concept of the regular PCR C) typically utilizes two pairs of nested primers D) all of the above E) none of the above

D) all of the above

What can the CRISPR-cas9 system provide? A) deleting targeted DNA segments B) knocking-in targeted DNA segments C) gene editing to correct a point mutation D) all of the above E) none of the above

D) all of the above

Zinc finger nuceleases (ZFN) are encoded by engineered genes, and they are synthetic proteins that _____________. A) contain zinc finger DNA binding domains B) contain the endonuclease domain of the Fok1 restriction enzyme C) can be engineered to recognize a variety of DNA sequences D) all of the above E) none of the above

D) all of the above

Two new pure-breeding strains of mouse (strain 1 and strain 2) have been obtained. Crosses between strain 1 and wild type, as well as crosses between strain 2 and wild type and between strain 1 and strain 2 always produce 100% wild-type mice. What kind(s) of interactions can be deduced from these results show? A) complementation only B) dominance only C) epistasis only D) complementation and dominance E) complementation, epistasis, and dominance

D) complementation and dominance

In the fruitfly Drosophila melanogaster, red and yellow pigments are synthesized through the pathway. These, plus the brown pigment synthesized through the ommochrome pathway, produce the dark red Drosophila eye color. A part of the pathways (simplified) is shown below (enzyme 1) (enzyme 2) Colorless Compound ------> colorless intermediate ----> red pigment (enzyme 1) (enzyme 3) Colorless Compound ------> colorless intermediate ----> yellow pigment Consider the genes encoding Enzyme 1 ("e1"), Enzyme 2 ("e2") and Enzyme 3 ("e3"), respectively. What are their predicted genetic interactions? A) e1 is recessively epistatic to e2, and e2 is recessively epistatic to e3 B) e1 is recessively epistatic to e3, and e3 is recessively epistatic to e2 C) e3 is recessively epistatic to e1, and e2 is recessively epistatic to e1 D) e1 is recessively epistatic to e2 and to e3 E) e2 is recessively epistatic to e1 and to e3

D) e1 is recessively epistatic to e2 and to e3

Targeted gene knockout using crossovers between homologous DNA molecules is often species specific. Among yeast, Drosophila, C. elegans, and mouse, which of the following is true. A) genes of yeast, Drosophila, C. elegans, and mouse can all be targeted by using crossovers B) genes of yeast, Drosophila, and mouse can all be targeted by using crossovers C) genes of yeast, C. elegans, and mouse can all be targeted by using crossovers D) genes of yeast and mouse can be targeted by using crossovers E) genes of Drosophila and C. elegans can be targeted by using crossovers

D) genes of yeast and mouse can be targeted by using crossovers

In recombinant DNA technology, DNA is most often cut using A) DNA ligase B) DNA polymerase C) DNA gyrase D) restriction endonucleases E) terminal transferase

D) restriction endonucleases

The GAL4 enhancers are located _______ of the genes they regulate and are known as __________. A) downstream; downstream activation sequences (DAS) B) downstream; downstream enhancer sequences (DES) C) upstream; upstream activation sequences (UAS) D) upstream; upstream enhancer elements (UES) E) None of the above

D) upstream; upstream enhancer elements (UES)

The Gal4 protein has which of the following functional domains? A. A DNA-binding domain B. An activation domain C. A repressor domain D. A and B E. A and C

D. A and B

Epigenetics could cause gene silencing through A. DNA methylation B. histone modification C. non-coding RNA, e.g., miRNA, siRNA D. all of the above E. none of the above

D. all of the above

In addition to yeast cells, Gal 4 has been shown to activate transcription in A. insect cells B. mouse cells C. human cells D. all of the above E. none of the above

D. all of the above

Retroviruses replicate using: A. DNA polymerase B. RNA polymerase C. restriction endonuclease D. reverse transcriptase E. topoisomerase

D. reverse transcriptase

Which of the following mutagenic systems requires no preexisting genetic manipulation system? A) Yeast knockout B) mouse knockout C) RNAi D) P element insertional mutagenesis E) CRISPR-cas9

E) CRISPR-cas9

After the excision of a P element, the donor site may experience A) loss of the entire original P element B) retain of partial P element sequence C) loss of the genomic sequences flanking the insertion D) DNA gap repair E) all of the above

E) all of the above

Transposons are genetically engineered to... A) express proteins encoded by cDNAs B) express RNAi constructs C) mutagenize gens D) produce germ line transformation E) all of the above

E) all of the above

Among the following mutations, which one has a "dominant look" but is actually a recessive allele? A) amorphic allele B) neomorphic allele C) hypomorphic allele D) dominant negative allele E) haplo-insufficient allele

E) haplo-insufficient allele

A CRISPR-cas system is a part of A) native cellular gene-editing function to create novel cellular functions B) entirely genetically engineered molecular function C) human cellular network to maintain genome integrity D) all of the above E) none of the above

E) none of the above

Site-specific recombination systems, Cre-lox and FLR/FRT, have several common properties. Which of the following statements is NOT true? A) the systems have specific target sequences B) their targets are palindromic C) they are derived from microorganisms D) all of the above E) none of the above

E) none of the above

Retrotransposons move via an intermediate that is: A. a double-stranded lollipop B. a retrovirus C. double-stranded RNA D. single stranded DNA E. single-stranded RNA

E. single-stranded RNA

Explain the difference between forward and reverse genetics in the genetic study of traits and biological characteristics.

Forward uses differences between mutant nd wild type, crosses and pedigrees used to understand genes involved in phenotypic effects if DNA is changed.

What are two most significant factors in selecting the attP sites?

Gal4, PhiC31 integrase

When targeting the worm myosin gene w/RNAi, dsRNA from the myosin gene is injected into the gonad, and mutant paralyzed worms are produced. Could you inject the Drosophila myosin dsRNA into the fly gonad to produce mutant flies? Explain your prediction

Mutants are not produced but rather phenocopies RNA is cell autonomous so only cells with mutant genotype would show mutant phenotypes

Paracentric inversion: Name the products after meiosis

Paracentric inversion doesn't include the centromere - products include a dicentric bridge, an acentric fragment, and two chromosomes with standard and inverted gene orders

Pericentric inversion: Name the products after meiosis

Pericentric inversion: inversion including the centromere - products include 2 chromosomes with the standard and inverted gene order, and two duplication/deletion products (1+ loci have been duplicated or deleted where the crossover has occurred wrt inverted region)

Compare the similarities and differences between the site-specific recombination systems and the PhiC31 integrase system

PhiC31 integrase system does not have a reverse reaction.

After a targeted mutagenesis in flies, no mutant phenotype for a gene is observed, What are the possible reasons for the absence of the mutant phenotype

Post transcriptional gene silencing - RNA degradation mechanisms that show similarities to RNAi - possibly naturally resistance toward virus - involve dsRNA, spread w/ in the organism from a localized initiating area, correlated with accumulation of siRNA

Molecular bar code method in yeast and RNAi mutagenesis are both used to carry out targeted genome-wide mutagenesis. What is the most fundamental difference between these 2 methods?

RNAi you don't create a mutant, and the worm still has an intact and unmutated gene, more specifically, the product of an RNAi mutagenesis is a phenocopy since it only copies the phenotype. Molecular bar code, you take the sequence and amplify the bar codes to later hybridize them onto microarrays to then look for absences

Which of the following organisms can be made transgenic by injection of DNA into the gonad, to generate extrachromosomal arrays of the transgene in some egg cells? A) Mouse (Mus musculus) B) Yeast (Saccaromyces cerevisiae) C) Bacteria (Escherichia coli) D) Humans (Homo sapiens) E) Roundworm (Caenorhabditis elegans)

Roundworm (Caenorhabditis elegans)

Compare and contrast autonomous and nonautonomous transposable elements

They both contain inverted terminal repeats autonomous elements encode functional transposase enzymes nonautonomous elements do no encode function enzymes and are rather made up of point mutations or more likely deletions that eliminate its function

What is the original organism where the Gal4/UAS system exists?

Yeast

What are the similarities and differences of the life cycles between retrotransposons and DNA transposons?

abundant in mammalian genomes - replicate in the same cell where the original copies reside

Hair pin RNA

artificial RNA molecule used to silence target gene expression via RNAi, accomplished via delivery of plasmids

What are the main segments in the knockdown vector, pvalium10? what are their functions?

attB, vermilion, Hsp70, MCS, gypsy, 2x LoxP sites, 5x UAS sites attB: a short DNA sequence corresponding to the crossover region where strand exchange takes place vermilion: marker gene, a mutant used to mark that the mutation was successful hsp70: important for protein folding, and help protect cells from stress MCS: membrane contact sites, for communication between cells gypsy: transposable elements that encodes gene products supposedly homolgous to retroviral proteins 2x LoxP sites: a site on a bacteriophage that allows for translocation events to be catalyzed by Cre induced recombination 5x UAS sites: tissues specific expression, short section of the promoter region

Why is a conditional mutation important in learning the function of a gene?

can use restrictive conditions to figure out specific functions of genes under restrictive conditions

When one uses a tissue-specific driver, i.e., ey-Gal4, what types of phenotypes could be observed? examples include ey-Gal4 > UAS-RNAi - +KV

different color eyes, eyes absent, different bristle

Advantages of using PhiC31

efficiency, unidirectional integration, no cofactor requirements, high levels of long-term transgene expression, and no insert size limitations

What are the similarities and differences of the genes between retrotransposons and retroviruses

functional envelope (env)gene in retroviruses -->absent or nonfunctional in LTR retrotransposons Retrovirus: -LTR-gag-pol-env- LTR- Retrotransposon: - LTR- gag-poly-LTR-

What can the replication slippage model be used to explain?

genome rearrangment

germline mutations vs. conditional mutations:

germline mutations: knownout, knockdown, knock-up - Issues: Essential genes, pleitropic activities (early/later functions), redundant pathways/functional redundancy - Passed to offspring Conditional mutations: knockdown, knock-up, RNA interference - mutant phenotype under certain "restrictive" conditions

What is the PhiC31 integrase system?

integrate specific RNAi constructs

What is the diagnostic cytological feature that is used to identify chromosomal inversions?

inversion loops, reduction of recombination frequency, and reduced fertility from unbalanced or deleted meiotic products

Diagram the pairing structure of the inversion heterozygous abcdefg/acfedcg. Assume the centromere is to the left of a. Is this a paracentric or pericentric inversion?

paracentric

Where can a SNP be called a polymorphism rather than a private variant?

polymorphism= SNP frequency of >1%

When one uses a ubiquitious driver, act5C-Gal4, to individually express UAS-RNAi transgenes in a genome wide collection, what different types of phenotypes could be observed?

repression of male specific structural genes

Why is it important to select optimal attP insertion sites?

to avoid the variability associated w/some P-element-based approaches; i.e. integration into transcriptionally inactive genes

What is the conceptual difference between traditional mutagenesis and genome-wide mutagenesis?

traditional mutagenesis is based on randomly induced mutations, frequency at which the same gene is mutated shows how many genes can be found genome-wide mutagenesis tests every gene but doesn't use statistical sampling, instead of mutates every gene based on the knowledge of tis DNA sequence

Balancers

used to maintain mutations in stable stocks as well as to prevent recombination and follow chromosomes in genetic mating schemes (special modified chromosomes)

What is the benefit of using a balancer chromosome?

used to prevent crossing over (genetic recombination)

Genetic drift

variation in the relative frequency of different genotypes in a small population, owing to the chance disappearance of particular genes as individual die or do not reproduce