Lecture 8 (woefully incomplete)

Question 1

Simple transcription unit

Answer 1

Control regions —-> exons and introns —-> poly-A site

Control regions can be 50,000 base pairs apart. They allow for tissue specificity and timing control.

Question 2

Complex transcription unit

Answer 2

Control regions —-> exon and introns interspersed among multiple cap sites and poly-A sites

Multiple sites allow for differential splicing

Question 3

Exon duplication is a consequence of ______________.

Answer 3

Unequal crossing over during recombination

Question 4

dscam (3 facts)

Answer 4

Down Syndrome Cell Adhesion Molecule

Useful in immune system and, uh, cell adhesion.

Alternative splicing allows for >40,000 different isoforms

Question 5

Protein families resulting from gene duplication and subsequent evolution (3)

Answer 5

β-globin, hox, tubulin

Question 6

Tool used to measure sequence alignment (and genetic disorder characterized through its use)

Answer 6

BLAST, neurofibromatosis type 1 (NF1)

Question 7

Orthologous genes

Answer 7

Genes of similar sequence that serve similar functions in different species

e.g. α-tubulins of human and fly

Question 8

Paralogous genes

Answer 8

Genes of similar sequence that serve different functions in the same species

e.g. α-tubulin and β-tubulin of human

Question 9

Non-polyglutamine disease

Answer 9

Genetic disease caused by microsatellite repeats outside of exons

e.g. Fragile X syndrome

Question 10

Polyglutamine disease

Answer 10

Genetic disease caused by microsatellite repeats in coding sequence

e.g. Huntington’s disease

Question 11

Two types of transposons

Answer 11

DNA transposon- DNA intermediate leaves original location and reinserts elsewhere

Retrotransposon- RNA intermediate from original DNA position is used by reverse transcriptase to form DNA intermediate, which inserts into new position

Question 12

DNA transposon formation (3 steps)

Answer 12

Donor DNA is cut bluntly and contains inverted repeats

Transposase coded in donor DNA makes staggered cuts in target DNA and ligates into target staggered strands

Cellular DNA polymerase finishes the ligation

Question 13

Two types of retrotransposons

Answer 13

non-LTR retrotransposon

Long terminal repeats (LTR) retrotransposon

Question 14

Formation of non-LTR retrotransposon

Answer 14

UNDER CONSTRUCTION

Question 15

Formation of LTR retrotransposon

Answer 15

UNDER CONSTRUCTION