SRC kinase signaling inhibitor 1

SRCIN1 (SRC kinase signaling inhibitor 1) is a negative regulator of SRC tyrosine kinase that functions by activating CSK, thereby suppressing SRC-mediated cell spreading and migration (UniProt: Q9C0H9). The protein also regulates dendritic spine morphology and participates in calcium-dependent exocytosis, suggesting roles in synaptic maintenance and neurotransmitter release.

In the central nervous system, SRCIN1's involvement in dendritic spine dynamics and synaptic processes positions it within pathways critical for neuronal communication and plasticity. UniProt records no inherited disease association for this protein.

SRCIN1 is downregulated in Alzheimer's Disease brain tissue relative to age-matched controls (mean log2FC −0.34; Chaparral AD proteomics). This decrease was observed across human post-mortem AD brain samples analyzed by TMT-labeled tandem mass spectrometry across multiple subcellular fractions. The modest but consistent reduction suggests impaired synaptic regulatory capacity in AD pathology, though the functional significance of SRCIN1 loss remains to be clarified in disease-specific contexts.