UCF Immunology Somatic Recombination Videos

somatic recombination

V-D-J reation of variable regions domains of heavy and light chain on antibody. ONLY B cells

heavy chain locus

Chromosome 14. 40V. 23D 6J.

allelic exclusion

only going to make one heavy chain gene and one light chain gene

heavy chain

middle with four domains. 2 attempts: maternal and paternal

light chain

outside with two domains

per domain

3 CDR and HVs

constant domain for heavy chain

three on the bottom coded for downstream on the 3 prime end

light chain

only v and j segment. can have multiple attempts b/c nothing cuts out

germline configuration

intervening dna segments between gene segments separated

V

variable gene segemnt

D

diversity gene segement

J

joining gene segment

functional gene

VDJ in heavy chain

lymphocyte specific enzymes

RAG 1, RAG 2, TdT only in developing t and b cells

RAG 1 and 2

needed for double strand break and alignment only in B and T cells in maturation

RAG complex

binds to and cleaves recombination signal sequences (RSS) to yield a DNA hairpin

RSS

heptamer and nonamer provide landing site for RAG I and II aka VDJ recombinase on each side of V D and J

palindromic (P) nucleotides

single strand after moving double strand, looks like hair pins

TdT

come in and bind and start adding nucleotide randomly until base paring

n-nucleotide addtion

non-templated nucleotides

junctional diversity

P and N nucleotide additions create this

junctional diversity

code for CDR 3. between v and d, all of d, and between d and j

V segment chosen

CDR 1 and 2