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We have cloned and characterized members of a novel family of proteins, the GGAs. These proteins contain an NH(2)-terminal VHS domain, one or two coiled-coil domains, and a COOH-terminal domain homologous to the COOH-terminal "ear" domain of gamma-adaptin. However, unlike gamma-adaptin, the GGAs are not associated with clathrin-coated vesicles or with any of the components of the AP-1 complex. GGA1 and GGA2 are also not associated with each other, although they colocalize on perinuclear membranes. Immunogold EM shows that these membranes correspond to trans elements of the Golgi stack and the TGN. GST pulldown experiments indicate that the GGA COOH-terminal domains bind to a subset of the proteins that bind to the gamma-adaptin COOH-terminal domain. In yeast there are two GGA genes. Deleting both of these genes results in missorting of the vacuolar enzyme carboxypeptidase Y, and the cells also have a defective vacuolar morphology phenotype. These results indicate that the function of the GGAs is to facilitate the trafficking of proteins between the TGN and the vacuole, or its mammalian equivalent, the lysosome.

The dense-core vesicles (DCVs) of neuroendocrine cells are a rich source of bioactive molecules such as peptides, hormones, and neurotransmitters, but relatively little is known about how they are formed. Using fractionation profiling, a method that combines subcellular fractionation with mass spectrometry, we identified ∼1200 proteins in PC12 cell vesicle-enriched fractions, with DCV-associated proteins showing distinct profiles from proteins associated with other types of vesicles. To investigate the role of clathrin in DCV biogenesis, we stably transduced PC12 cells with an inducible shRNA targeting clathrin heavy chain, resulting in ∼85% protein loss. DCVs could still be observed in the cells by electron microscopy, but mature profiles were ∼4-fold less abundant than in mock-treated cells. By quantitative mass spectrometry, DCV-associated proteins were found to be reduced ∼2-fold in clathrin-depleted cells as a whole and ∼5-fold in vesicle-enriched fractions. Our combined datasets enabled us to identify new candidate DCV components. Secretion assays revealed that clathrin depletion causes a near-complete block in secretagogue-induced exocytosis. Taken together, our data indicate that clathrin has a function in DCV biogenesis beyond its established role in removing unwanted proteins from the immature vesicle.

From a review of the literature it appears that occupational therapists (OTs) have been less actively involved in the treatment of clients with eating disorders in the last 10 years. With the job markets changing for OT, it is important to understand the factors influencing therapists' involvement in this area. One factor that may limit the number of therapists working with clients with eating disorders may be the limited understanding of and lack of referrals to OT by psychologists. This study investigates whether psychologists perceive that OTs provide beneficial treatments for clients with eating disorders and if they would refer eating disorder clients to OTs. This study also aims to identify if there are similar treatment models and techniques used by both OTs and psychologists in treating this population. Surveys were sent to 75 members of the New York State Psychological Association who had self-identified as treating eating disorders. An effective return rate of 44% was achieved. The resu...