The Sodium-hydrogen Exchanger Nhx1 Drives Late Endosome- Vacuole Membrane Fusion
نویسنده
چکیده
منابع مشابه
Human Na(+)/H(+) exchanger isoform 6 is found in recycling endosomes of cells, not in mitochondria.
Since the discovery of the first intracellular Na(+)/H(+) exchanger in yeast, Nhx1, multiple homologs have been cloned and characterized in plants. Together, studies in these organisms demonstrate that Nhx1 is located in the prevacuolar/vacuolar compartment of cells where it sequesters Na(+) into the vacuole, regulates intravesicular pH, and contributes to vacuolar biogenesis. In contrast, the ...
متن کاملThe sodium/proton exchanger Nhx1p is required for endosomal protein trafficking in the yeast Saccharomyces cerevisiae.
We show that the vacuolar protein sorting gene VPS44 is identical to NHX1, a gene that encodes a sodium/proton exchanger. The Saccharomyces cerevisiae protein Nhx1p shows high homology to mammalian sodium/proton exchangers of the NHE family. Nhx1p is thought to transport sodium ions into the prevacuole compartment in exchange for protons. Pulse-chase experiments show that approximately 35% of t...
متن کاملEndosomal Na+ (K+)/H+ exchanger Nhx1/Vps44 functions independently and downstream of multivesicular body formation.
The multivesicular body (MVB) is an endosomal intermediate containing intralumenal vesicles destined for membrane protein degradation in the lysosome. In Saccharomyces cerevisiae, the MVB pathway is composed of 17 evolutionarily conserved ESCRT (endosomal sorting complex required for transport) genes grouped by their vacuole protein sorting Class E mutant phenotypes. Only one integral membrane ...
متن کاملMutational analysis of the intramembranous H10 loop of yeast Nhx1 reveals a critical role in ion homoeostasis and vesicle trafficking.
Yeast Nhx1 [Na+(K+)/H+ exchanger 1] is an intracellular Na+(K+)/H+ exchanger, localizing to the late endosome where it is important for ion homoeostasis and vesicle trafficking. Phylogenetic analysis of NHE (Na+/H+ exchanger) sequences has identified orthologous proteins, including HsNHE6 (human NHE6), HsNHE7 and HsNHE9 of unknown physiological role. These appear distinct from well-studied mamm...
متن کاملThe Na+(K+)/H+ exchanger Nhx1 controls multivesicular body-vacuolar lysosome fusion.
Loss-of-function mutations in human endosomal Na+(K+)/H+ exchangers (NHEs) NHE6 and NHE9 are implicated in neurological disorders including Christianson syndrome, autism, and attention deficit and hyperactivity disorder. These mutations disrupt retention of surface receptors within neurons and glial cells by affecting their delivery to lysosomes for degradation. However, the molecular basis of ...
متن کامل