Antibody Structure and Function 1

Question 1

Allelic exclusion

Easy def

Answer 1

Both chromosomes start - first one to do it wins

Question 2

Allelic exclusion

Hard def

Answer 2

Successful rearrangement of one allele for each chain inhibits rearrangement of the other alleles

Question 3

What is the inhibition of rearrangement due to?

Answer 3

Signalling thru the Pre-BCR (stops H)

BCR (stops L)

Question 4

How can some Ig molecules have identical Ag specificity but possess different C region characteristics?

Answer 4

Ig molecules with differing C regions are generated thru isotype Class Switch Recombination

Question 5

S = switch region

Answer 5

Tells where to cut

Question 6

Which isotype is not produced from Class switch recombination?

Answer 6

IgD - Alternative splicing

Question 7

Class switching is permanent but..

Answer 7

we can undergo lots if there are constant genes down the chromosome

Question 8

Isotype class switch involves what type of arrangement event?

Answer 8

Dna - permanent

Question 9

Where is the switch region?

Answer 9

5’ to the desired Ig C segment

Question 10

What happens to the intervening Dna in class switch recomb?

Answer 10

it is lost

Question 11

What enzyme is required or class switch?

Answer 11

(AID) Activation-Induce Cytidine Deaminase

Question 12

What does AID induce?

Answer 12

Single strand breaks or nicks in the DNA

Question 13

What does a deficiency in AID result in?

Answer 13

hyper-IgM syndrome
Can't make anything but IgM - can't undergo class switch

Question 14

What are the 2 functional regions?

Answer 14

Variable and Constant

Question 15

What two things do the variable region do?

Answer 15

1. Mediate Ag binding

2. Differ b/w Ig

Question 16

What two things does the constant region do?

Answer 16

1. Effector Functions

2. Conserved bw Ig of one isotype