CAPRIN1 is an RNA-binding protein that serves as a critical regulator of mRNA transport, translation, and stability, with essential roles in neurogenesis, synaptic plasticity, and cell proliferation 1. The protein functions as a key component in cytoplasmic stress granule formation through liquid-liquid phase separation mechanisms 23. CAPRIN1 undergoes phase separation upon binding target mRNAs, assembling them into cytoplasmic ribonucleoprotein granules that concentrate mRNAs with regulatory factors 4. In these granules, CAPRIN1 mediates recruitment of deadenylase complexes, leading to mRNA deadenylation and translational inhibition 1. The protein directly binds to specific mRNAs including MYC, CCND2, BDNF, and CAMK2A 1. CAPRIN1 haploinsufficiency causes a neurodevelopmental disorder characterized by language impairment, intellectual disability, ADHD, and autism spectrum disorder 1. In neuronal models, CAPRIN1 deficiency results in reduced neuronal processes, disrupted organization, impaired calcium signaling, and increased oxidative stress 1. The protein also interacts with FMRP in stress response pathways and plays roles in cancer biology through regulation of oncogene translation 546.