Lin-7 homolog A, crumbs cell polarity complex component (LIN7A)

Lin-7 homolog A (LIN7A) is a **scaffold protein** and a **component of the Crumbs cell polarity complex** involved in the organization and maintenance of *apico-basal polarity* in epithelial cells and neurons[1][2][4][5][6]. LIN7A stabilizes and anchors various membrane proteins (such as ion channels, GABA transporter, NMDA receptor subunits, epidermal growth factor family receptors) at specific plasma membrane domains, and is essential for compartmentalization in polarized cells[2][4][5]. In neurons, LIN7A is key for synaptic vesicle transport and localization of synaptic components. In epithelial tissues, it helps maintain *cell polarity* and organizes cell junctions. Overexpression of LIN7A disrupts epithelial glandular structure, increases proliferation via MEK/ERK and PI3K/AKT pathways, and promotes invasion and abnormal cell polarity—these changes are implicated in breast carcinogenesis, specifically in invasive micropapillary carcinoma[1]. LIN7A is associated with intellectual disability and autism spectrum disorder[2][4]. No approved drugs directly target LIN7A, and it is not currently considered a therapeutic target in clinical practice.

Other names

Lin-7AMALS1VELI1protein lin-7 homolog AhLin-7MALS-1TIP-33Vertebrate lin-7 homolog 1Mammalian lin-seven protein 1Tax interaction protein 33crumbs cell polarity complex component