LYN

LYN
Identifiers
Symbol	?
NCBI gene	4067
HGNC	6718
OMIM	165120
RefSeq	NM_002350
UniProt	P07948
Search for Structures Swiss-model Domains InterPro

LYN is a member of the Src family of tyrosine kinases, which are non-receptor protein tyrosine kinases involved in the regulation of cellular processes. LYN is encoded by the LYN gene located on chromosome 8q13.1 in humans. It plays a crucial role in the signaling pathways of various cell types, particularly in the immune system.

Structure

LYN is a protein composed of several domains that are characteristic of Src family kinases. These include:

• An N-terminal SH3 domain, which mediates protein-protein interactions.
• An SH2 domain, which binds to phosphorylated tyrosine residues on other proteins.
• A kinase domain, which is responsible for its enzymatic activity.
• A C-terminal regulatory domain.

Function

LYN is involved in the regulation of several cellular processes, including:

• Cell proliferation
• Cell differentiation
• Apoptosis
• Immune response

In the immune system, LYN is particularly important in B cell receptor (BCR) signaling. It acts as an initiator of the BCR signaling cascade by phosphorylating the immunoreceptor tyrosine-based activation motifs (ITAMs) on the cytoplasmic tails of the BCR complex.

Clinical Significance

Dysregulation of LYN activity has been implicated in various diseases, including:

• Chronic myelogenous leukemia (CML)
• Non-Hodgkin lymphoma
• Systemic lupus erythematosus (SLE)

In CML, LYN is often overexpressed and contributes to the proliferation of leukemic cells. In SLE, aberrant LYN signaling can lead to autoimmunity due to improper regulation of B cell activity.

Research and Therapeutic Targeting

LYN is a target for therapeutic intervention in diseases where its activity is dysregulated. Inhibitors of LYN kinase activity are being explored as potential treatments for certain types of cancer and autoimmune diseases.

Also see

• Src family kinases
• Tyrosine kinase
• B cell receptor
• Signal transduction