Antibody Diversity

Flashcards about Antibody Diversity and Gene Rearrangement

What process helps generate antibody diversity?

Mechanisms, including genetic rearrangements, that lead to antibody diversity.

What processes happen to antibodies?

Somatic hypermutation and class switching.

What are the genetic rearrangements for antibody production?

Heavy chains, Kappa, and Lambda.

What did Hozumi and Tonegawa demonstrate?

Variable and constant chains are encoded by different gene segments that are combined.

What segment was identified in light chains?

The joining (J) segment.

What encodes the heavy chain?

Multiple gene segments.

What are the key enzymes in heavy chain gene rearrangement?

Recombinase 1 and recombinase 2 (RAG1 and RAG2).

What happens during D-J and V-DJ joining?

Deletion of DNA between D3 and J2 and between V2 and D3.

What process leads to the creation of mRNA from a rearranged light chain gene?

Transcription and RNA splicing.

What are the key enzymes in kappa light chain gene rearrangement?

Recombinase 1 and recombinase 2 (RAG1 and RAG2).

What are the Key Enzymes for l light chain gene rearrangement?

Recombinase 1 and recombinase 2 (RAG1 and RAG2).

How many genetic rearrangements are there for Heavy, Kappa, and Lambda chains respectively?

V x D x J, V x J, V x J.

What type of recombination occurs in heavy chain genes?

VDJ recombination.

What gene goes under VJ recombination?

Light chain gene.

What is the order of Ig Heavy chains in B cell membrane expression?

None --> m --> m --> m+d

What is the order of Ig Light chains in membrane expression?

None --> Surrogate --> surrogatek or l --> k or l

What directs recombination?

Recombination signal sequences (RSS).

What enzyme joins gene segments?

RAG1/2 recombinase.

What does RAG stand for?

Recombination-activating gene.

What is the RAG1/2 complex responsible for?

Recognizing and cutting DNA at the immunoglobulin-encoding region and the RSS.

What are the key enzymes in end processing during antibody gene rearrangement?

Endonuclease, terminal deoxynucleotidyl transferse and repair enzymes.

What is the key enzyme in class switching?

Activation induced cytidine deaminase (AID).

What is the mechanism of class switching?

DNA Rearrangement

What enzyme is responsible for Class Switching?

Activation induced cytidine deaminase (AID).

What occurs during somatic hypermutation?

Mutations occur in these cells

What composes TCRa?

Va1 …. Va48 Vd Dd1-2 Jd1-3 Cd Ja1-Ja100 Ca

What composes TCRb?

V1 …. V~60 D J1-J6 C D J1-J7 C

What composes TCRg?

V1 J1 C1 J2 …. V8 C2

What happens during B cell development in the antigen-independent phase?

Order of gene rearrangements and expression of antibody.

What enzyme generates somatic hypermutation?

Recombinase 1 and recombinase 2 (RAG1 and RAG2)