Selective recognition, sorting, and localization of proteins to the degradative lysosome via vesicular carriers is an essential feature of all eukaryotic cells. Mislocalization of lysosomal proteases is associated with disease states including lysosomal storage diseases and cancer. Most lysosomal proteases are synthesized in the rough endoplasmic reticulum and transmit through the early secretory pathway en route to the lysosome; they diverge from secreted proteins at a trans-Golgi compartment. One major post-Golgi pathway to the lysosome involves the endosome which is responsible for uncoupling of lysosomal proteases from their receptors. While several genes and gene products have been identified that are involved in the lysosomal delivery of luminal hydrolases at the pre-endosome and endosome stages, post-endosomal events are relatively poorly defined. We propose to characterize post- endosomal steps in lysosomal delivery of luminal hydrolases using the yeast Saccharomyces cerevisiae. The yeast vacuole is functionally equivalent to the mammalian lysosome, and its carboxy peptidase Y (CPY)-pathway of vacuolar delivery parallels the mannose-6-phosphate pathway in mammalian cells. Yeast offers the advantage of well- developed genetics and molecular genetics. The objective of our studies is to define genes and gene products involved in the endosome to lysosome stage of targeting and delivery of luminal proteases that utilize the CPY-pathway. We have developed a novel mutant screen based on immunodetection of a maturation intermediate (p2CPY) of the vacuolar protease carboxypeptidase Y (mCPY). We have isolated mutants that exhibit internal p2CPY accumulation. The mutants display characteristics that indicate defects in endosome to vacuole delivery and process (env mutants).
Our specific aims are to characterize four env mutants genetically, microscopically and biochemically; to clone their putative ENV genes, and to begin molecular characterization of the cloned genes and their products.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Minority Biomedical Research Support - MBRS (S06)
Project #
5S06GM063119-02
Application #
6659291
Study Section
Minority Programs Review Committee (MPRC)
Project Start
2002-09-30
Project End
2003-09-29
Budget Start
Budget End
Support Year
2
Fiscal Year
2002
Total Cost
Indirect Cost
Name
California State University Long Beach
Department
Type
DUNS #
City
Long Beach
State
CA
Country
United States
Zip Code
90840
Nishiya, Casey T; Boxx, Gayle M; Robison, Kerry et al. (2016) Influence of IgG Subclass on Human Antimannan Antibody-Mediated Resistance to Hematogenously Disseminated Candidiasis in Mice. Infect Immun 84:386-94
Valinluck, Michael; Woraratanadharm, Tad; Lu, Ching-yu et al. (2014) The cell end marker Tea4 regulates morphogenesis and pathogenicity in the basidiomycete fungus Ustilago maydis. Fungal Genet Biol 66:54-68
Nelson, O Lynne; Rourke, Bryan C (2013) Increase in cardiac myosin heavy-chain (MyHC) alpha protein isoform in hibernating ground squirrels, with echocardiographic visualization of ventricular wall hypertrophy and prolonged contraction. J Exp Biol 216:4678-90
Kamei, Ayako; Hauser, Paul S; Beckstead, Jennifer A et al. (2012) Expressed protein ligation-mediated template protein extension. Protein Expr Purif 83:113-6
Nowell, Megan M; Choi, Hyung; Rourke, Bryan C (2011) Muscle plasticity in hibernating ground squirrels (Spermophilus lateralis) is induced by seasonal, but not low-temperature, mechanisms. J Comp Physiol B 181:147-64
Aoi, Mikio C; Rourke, Bryan C (2011) Interspecific and intragenic differences in codon usage bias among vertebrate myosin heavy-chain genes. J Mol Evol 73:74-93
Gharakhanian, Editte; Chima-Okereke, Onyinyechi; Olson, Daniel K et al. (2011) env1 Mutant of VPS35 gene exhibits unique protein localization and processing phenotype at Golgi and lysosomal vacuole in Saccharomyces cerevisiae. Mol Cell Biochem 346:187-95
Barrows, N D; Nelson, O L; Robbins, C T et al. (2011) Increased cardiac alpha-myosin heavy chain in left atria and decreased myocardial insulin-like growth factor (Igf-I) expression accompany low heart rate in hibernating grizzly bears. Physiol Biochem Zool 84:1-17
Shahed, Asha; Young, Kelly A (2011) Intraovarian expression of GnRH-1 and gonadotropin mRNA and protein levels in Siberian hamsters during the estrus cycle and photoperiod induced regression/recrudescence. Gen Comp Endocrinol 170:356-64
Valinluck, Michael; Ahlgren, Sara; Sawada, Mizuho et al. (2010) Role of the nuclear migration protein Lis1 in cell morphogenesis in Ustilago maydis. Mycologia 102:493-512

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