Reduced pigmentation (rp), a mouse model of Hermansky-Pudlak syndrome, encodes a novel component of the BLOC-1 complex |
| |
Authors: | Gwynn Babette Martina Jose A Bonifacino Juan S Sviderskaya Elena V Lamoreux M Lynn Bennett Dorothy C Moriyama Kengo Huizing Marjan Helip-Wooley Amanda Gahl William A Webb Lisa S Lambert Amy J Peters Luanne L |
| |
Affiliation: | The Jackson Laboratory, 600 Main St, Bar Harbor, ME 04609, USA. |
| |
Abstract: | Hermansky-Pudlak syndrome (HPS), a disorder of organelle biogenesis, affects lysosomes, melanosomes, and platelet dense bodies. Seven genes cause HPS in humans (HPS1-HPS7) and at least 15 nonallelic mutations cause HPS in mice. Where their function is known, the HPS proteins participate in protein trafficking and vesicle docking/fusion events during organelle biogenesis. HPS-associated genes participate in at least 4 distinct protein complexes: the adaptor complex AP-3; biogenesis of lysosome-related organelles complex 1 (BLOC-1), consisting of 4 HPS proteins (pallidin, muted, cappuccino, HPS7/sandy); BLOC-2, consisting of HPS6/ruby-eye, HPS5/ruby-eye-2, and HPS3/cocoa; and BLOC-3, consisting of HPS1/pale ear and HPS4/light ear. Here, we report the cloning of the mouse HPS mutation reduced pigmentation (rp). We show that the wild-type rp gene encodes a novel, widely expressed 195-amino acid protein that shares 87% amino acid identity with its human orthologue and localizes to punctate cytoplasmic structures. Further, we show that phosphorylated RP is part of the BLOC-1 complex. In mutant rp/rp mice, a premature stop codon truncates the protein after 79 amino acids. Defects in all the 5 known components of BLOC-1, including RP, cause severe HPS in mice, suggesting that the subunits are nonredundant and that BLOC-1 plays a key role in organelle biogenesis. |
| |
Keywords: | |
本文献已被 PubMed 等数据库收录! |
| 点击此处可从《Blood》浏览原始摘要信息 |
|
点击此处可从《Blood》下载免费的PDF全文 |
|