|Detection of Human, Mouse, and Rat GULP1/CED-6 by Western Blot. Western blot shows lysates of K562 human chronic myelogenous leukemia cell line, MEF mouse embryonic feeder cells, and Rat‑2 rat embryonic fibroblast cell line. PVDF membrane was probed with 1 µg/mL of Sheep Anti-Human/Mouse/Rat GULP1/CED-6 Antigen Affinity-purified Polyclonal Antibody (Catalog # AF7978) followed by HRP-conjugated Anti-Sheep IgG Secondary Antibody (Catalog # HAF016). A specific band was detected for GULP1/CED-6 at approximately 36 kDa (as indicated). This experiment was conducted under reducing conditions and using Immunoblot Buffer Group 1.|
GULP1 (also PTB domain-containing engulfment adaptor protein 1 and Cell death protein 6 homolog/CED6) is a 36-40 kDa, cytosolic member of the ced-6 family of proteins. It is expressed by multiple cell types, including macrophages, neurons and sinusoidal endothelial cells, and is believed to play a key role in phaogcytosis, particularly involving apoptotic cells. Failure to remove apoptotic cells is suggested to contribute to chronic inflammatory conditions. GULP1 is involved with a MEGF10:GULF:stabilin-1:stabilin-2 internalization pathway. Possibly following endosome formation, it binds to transmembrane activated stabilins and/or LRP1 as a homodimer, and serves as an intermediate for signal transduction. GULP1 also binds to APP, facilitating its proteolysis and the generation of A beta. Human GULP1 is 304 amino acids (aa) in length. It contains one PTB domain (aa 17-154) that interacts with transmembrane receptors, a Leu-zipper (aa 163-193) that mediates dimerization, and a Pro-rich region (aa 238-271) that is likely involved with signal transduction. There are three splice variants. One shows a deletion of aa 31-133, a second contains a 34 aa substitution for aa 134-304, and a third contains a 10 aa substitution for aa 282-304. Over aa 1-92, human GULP1 shares 99% aa sequence identity with mouse GULP1.