Leptin receptor overlapping transcript-like 1 (LEPROTL1)

Leptin receptor overlapping transcript-like 1 (LEPROTL1), also known as endospanin-2, is a membrane-associated protein homologous to yeast VPS55 and vertebrate endospanins, structurally characterized by a four-helix transmembrane bundle[1]. LEPROTL1 is not a cell surface receptor but is instead localized to endosomal and trans-Golgi compartments, functioning mainly in the regulation of intracellular protein trafficking and controlling the cell surface expression of certain receptors, notably the growth hormone receptor[2][3]. LEPROTL1 negatively regulates growth hormone signaling by promoting the turnover or endosomal retention of the growth hormone receptor, thus reducing its abundance at the cell membrane, a function particularly relevant in liver during periods of nutrient deprivation[2][3]. It is also implicated in the endosome-to-vacuole transport pathway, and interacts with vesicle trafficking-related proteins such as Rab13 and Rab8 as part of the broader endospanin family[1]. LEPROTL1 has no reported direct links to actionable drug targets or biomarker use, and although mutations in related intracellular trafficking pathways may play a role in some rare diseases, direct genetic linkage is currently known only for metaphyseal chondrodysplasia, Schmid type[2]. LEPROTL1 is distinct from the classical leptin receptor (LEPR), though both are encoded by related genes and may have coordinated roles in the modulation of leptin and other receptor signaling[1]. The gene is highly conserved across eukaryotes, suggesting an ancient and fundamental role in vesicular trafficking. It is expressed in many tissues but is not deemed a conventional therapeutic target since no drugs are known to interact with it[2][3][5].

Other names

Leptin receptor overlapping transcript-like 1LEPROTL1My047UNQ577/PRO1139Vps55Endospanin-2HSPC112LERL1