Antigen Receptor Quiz

Describe Heavy and Light chains

they are identical each with varbiable and constant domains

Which chain has a longer constant region

heavy chain

what is the antigen binding pocket

where the 2 heavy and light chains meet where the antigen comes into contact

What is the variable region generated of

taking a V D and J segment and mixing/matching

Is VDJ permanent

Yes, the og DNA is lost

what chain only has V and J segemnts

Light Chain

Rule for RSS

only rearrange 23 RSS with 12 RSS

what are RAG proteins

Recombination Activation genes

where is the active region of RAG1 (more aa)

C-terminal and DDE motif site

where is the active region for RAG2

N-terminal core

What does RAG1 do

Binds the DNA (recognizing RSS) and cleaves the DNA

What does RAG2 do

Steers RAG1 towards correct cleaving site and activates RAG 1

WHat 3 things make all the types of antigen receptors

Gene segment combinational joining, junctional diversification (third hypervaribale region), combination of L and H chains

How do B cells become more effective

by introducing millions of mutations and whichever binds the best is the most effective.

IgM ǔ

Activates compliment

IgD Ş

Development of tolerance

IgG y

activates compliment

IgA ā

found in secretions

IgE Ę

allergic responses

What is the most abundant antibody

IgG

what 2 antibodies are coexpressed

IgM/D via alternative splicing

is class switching permanent

YES

transcription is needed for class switching at switch regions but what happens

a ds break and the change in constant regions

Single stranded DNA is catalyized / initialized by what

AID

What is AID

Turns cytidine into uridine during class switching

does AID work on ds DNA

NO

by changing c to u what happens

UNG removes the uracil which leads to a nick in the DNA

multiple single strang nicks makes what

ds break

does class switching increase antigen receptor diversity?

NO

what increases the antigen receptor diversity

Somatic hypermutatiuon

What triggers hypermutation

AID

When DNA breaks

wrong bits of DNA can be joined or oncogenes can join onto DNA leading to cancer

What is cryptic Recombination

oncogene joined with V or J segment

End donation

broken end on a chromsome binds to oncogene

BCL-2/igH

most common transloaction in human cancer

Re-integration

when two RSS accidentally bind?