The domain within your query sequence starts at position 141 and ends at position 227; the E-value for the C2-set_2 domain shown below is 6.2e-8.

ATSSDIQILMHTPNIKGVMLECHSGGWFPQPHMEWRNSKGEVIQATSKFHSQDKNKLFNM
SMVLFIEASSHRNVICYFQNLVTHQEQ

C2-set_2

C2-set_2
PFAM accession number:PF08205
Interpro abstract (IPR013162):

The basic structure of immunoglobulin (Ig) molecules is a tetramer of two light chains and two heavy chains linked by disulphide bonds. There are two types of light chains: kappa and lambda, each composed of a constant domain (CL) and a variable domain (VL). There are five types of heavy chains: alpha, delta, epsilon, gamma and mu, all consisting of a variable domain (VH) and three (in alpha, delta and gamma) or four (in epsilon and mu) constant domains (CH1 to CH4). Ig molecules are highly modular proteins, in which the variable and constant domains have clear, conserved sequence patterns. The domains in Ig and Ig-like molecules are grouped into four types: V-set (variable; IPR013106), C1-set (constant-1; IPR003597), C2-set (constant-2; IPR008424) and I-set (intermediate; IPR013098) [(PUBMED:9417933)]. Structural studies have shown that these domains share a common core Greek-key beta-sandwich structure, with the types differing in the number of strands in the beta-sheets as well as in their sequence patterns [(PUBMED:15327963), (PUBMED:11377196)].

Immunoglobulin-like domains that are related in both sequence and structure can be found in several diverse protein families. Ig-like domains are involved in a variety of functions, including cell-cell recognition, cell-surface receptors, muscle structure and the immune system [(PUBMED:10698639)].

This entry represents the C2-set type domains found in the T-cell antigen CD80, as well as in related proteins. CD80 (B7-1) is a glycoprotein expressed on antigen-presenting cells [(PUBMED:10661405)]. The shared ligands on CD80 and CD86 (B7-2) deliver the co-stimulatory signal through CD28 and CTLA-4 on T-cells, where CD28 augments the T-cell response and CTLA-4 attenuates it [(PUBMED:11279502)].

This is a PFAM domain. For full annotation and more information, please see the PFAM entry C2-set_2