Lymphocyte-specific protein (IPR002211)

Short name: Lymphspecific

Overlapping homologous superfamilies


Family relationships


Human and mouse LSP1 proteins consist of two domains: an N-terminal acidic domain and a C-terminal basic domain [PMID: 2295815, PMID: 3263441]. The C-terminal domains are highly conserved and include several putative Ser/Thr phosphorylation sites [PMID: 2295815]. Immunoprecipitation of LSP1 from 32P-orthophosphate-loaded cells indicates that LSP1 is a phosphoprotein [PMID: 2295815]. The N-terminal domain of mouse LSP1 contains two putative Ca2(+)-binding sites, but these are not conserved in human LSP1; nevertheless, a different Ca2(+)-binding site may exist in the human protein, indicating functional rather than strict sequence conservation of the two proteins [PMID: 2295815, PMID: 3263441].

Although the precise function of LSP is unclear, it is an F-actin binding protein thought to be involved in transmembrane signal transduction via its postulated calcium-binding function [PMID: 7935501] (although evidence for the existence of the calcium-binding sites is weak). The expression pattern of LSP1 is highly restricted. Non-lymphoid cell lines or normal mouse tissues such as brain, lung, liver, skeletal muscle, kidney or testis do not express the protein, and it appears that its expression in the hematopoietic system is restricted to the lymphocyte, macrophage and neutrophil lineages [PMID: 7935501].

GO terms

Biological Process

GO:0007165 signal transduction

Molecular Function

GO:0003779 actin binding

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.