BIOL 2050U Lecture Notes - Themis, Immunoglobulin Class Switching, Exon
Document Summary
Antibody sequence variability is clustered variability = # of different observed aa"s/ frequency of most common range = 1(least) 400(most) observe clustering in 3 hypervariable regions interspersed by framework regions true for light and heavy chains. **hypervariable regions involved in antigen binding** also called cdr"s (complementarity determining regions) 3d structure of antibody domains: all domains have immunoglobulin fold all fold independently and there is interaction between hc and lc (vh interacts w/ vl) hypervariable regions cap the distal end. 3d structures of antibody/ligand binding: larger proteins more interaction (more cdr"s involved) framework residues contact somewhat large interacting surfaces w/ high steric complementarity hydrophobics/h-bonds are v. important. Epitope = minimal amt of antigen needed to bind antibody. Hc and lc are coded piecewise brought together by site specific recombination during b-cell differentiation. Lc: vj segment not separated by introns at dna level preceded and followed by introns that are spliced during txn (1 recombination)
