Leptin
Leptin, as listed on this page, refers to the product of the LEPROT gene (leptin receptor overlapping transcript), also known as leptin receptor gene-related protein, OBRGRP, OB-RGRP and VPS55. It is a Golgi and endosome membrane protein that lowers cell surface levels of the leptin receptor and the growth hormone receptor. Browse Assay Genie's current range of Leptin research reagents below, or read on for the biology behind the target.
The Leptin target on this page is the leptin receptor gene-related protein encoded by LEPROT, and it should not be confused with the secreted hormone leptin itself. Its main role is to act as a negative regulator of the leptin receptor (LEPR). By decreasing LEPR expression at the cell surface, it reduces the response of a cell to leptin. It also negatively regulates growth hormone (GH) receptor expression at the cell surface in liver, and it may contribute to liver resistance to GH during periods of reduced nutrient availability.
The protein is associated with the Golgi apparatus and with endosomes, where it is found in the membrane. This localisation fits its function in controlling how much of each receptor reaches the cell surface, and so in altering receptor-mediated cell signalling. The NCBI Gene summary describes this effect on both the growth hormone receptor (GHR) and the leptin receptor, also called OBR, citing work by Couturier and colleagues in 2007 and Touvier and colleagues in 2009. Researchers studying the LEPROT gene or its protein product usually do so in the context of receptor trafficking and signalling.
The protein belongs to the OB-RGRP/VPS55 family, which is reflected in two of its aliases, OB-RGRP and VPS55. The name leptin receptor overlapping transcript, and the alias OBRGRP, point to its relationship with the leptin receptor gene. Mouse and rat both carry a Leprot ortholog, so the target can be examined in common rodent models of metabolism and endocrine signalling.
LEPROT negatively regulates leptin receptor cell surface expression, making it a useful subject for work on how cells tune their response to leptin.
LEPROT limits growth hormone receptor surface expression in liver and may contribute to hepatic GH resistance when nutrient availability is reduced.
As a Golgi and endosome membrane protein of the OB-RGRP/VPS55 family, it is relevant to studies of how receptors are routed to the cell surface.
By changing the amount of receptor at the cell surface, LEPROT alters downstream receptor-mediated signalling for both leptin and growth hormone.
LEPROT negatively regulates leptin receptor cell surface expression, which decreases the response to leptin. It also reduces growth hormone receptor surface expression in liver and may help explain liver resistance to GH when nutrients are scarce. It acts from Golgi and endosome membranes.
LEPROT stands for leptin receptor overlapping transcript. The protein is also called leptin receptor gene-related protein, and its aliases include OBRGRP, OB-RGRP, VPS55 and FLJ90360. It should be distinguished from the hormone leptin, which is a different gene product.
Yes. Mouse and rat each have an ortholog named Leprot, and the protein belongs to the OB-RGRP/VPS55 family. The name VPS55 reflects this family grouping. For antibody or ELISA work in other species, check the datasheet of any product for its validated reactivity.
Leptin and growth hormone receptors, their ligands and other targets linked to receptor signalling and metabolism.
Gene and protein annotations from HGNC, NCBI Gene and UniProt O15243; product specifications from Assay Genie datasheets.