Antibody Structure Problem Set

Problem 2. Antibody HV regions

Framework regions, subdivisions of antibody variable regions, are composed of beta sheets with fairly constant amino acids sequences. The variable region of light and heavy chains each have three hypervariable (HV) or complementarity determining regions (CDR) that show dramatic changes in amino acids when antibodies of different specificity are compared. From the exercise, what region of the antibody contacts antigen?

A.	framework regions of both light and heavy chains
B.	hypervariable regions of the light chain
C.	hypervariable regions of the heavy chain
D.	hypervariable regions of the light and heavy chains The HV regions of both the light and heavy chains are responsible for binding antigen.