ABSTRACT
A unifying feature of polycystin-2 channels is their localization to both primary and motile cilia/flagella. In Drosophila melanogaster, the fly polycystin-2 homologue, Amo, is an ER protein early in sperm development but the protein must ultimately cluster at the flagellar tip in mature sperm to be fully functional. Male flies lacking appropriate Amo localization are sterile due to abnormal sperm motility and failure of sperm storage. We performed a forward genetic screen to identify additional proteins that mediate ciliary trafficking of Amo. Here we report that Drosophila homologues of KPC1 and KPC2, which comprise the mammalian KIP1 ubiquitination-promoting complex (KPC), form a conserved unit that is required for the sperm tail tip localization of Amo. Male flies lacking either KPC1 or KPC2 phenocopy amo mutants and are sterile due to a failure of sperm storage. KPC is a heterodimer composed of KPC1, an E3 ligase, and KPC2 (or UBAC1), an adaptor protein. Like their mammalian counterparts Drosophila KPC1 and KPC2 physically interact and they stabilize one another at the protein level. In flies, KPC2 is monoubiquitinated and phosphorylated and this modified form of the protein is located in mature sperm. Neither KPC1 nor KPC2 directly interact with Amo but they are detected in proximity to Amo at the tip of the sperm flagellum. In summary we have identified a new complex that is involved in male fertility in Drosophila melanogaster.
Subject(s)
Infertility, Male/genetics , Ubiquitin-Protein Ligase Complexes/genetics , Animals , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Drosophila melanogaster , Female , Male , Membrane Proteins/genetics , Membrane Proteins/metabolism , Protein Binding , Spermatogenesis , Ubiquitin-Protein Ligase Complexes/metabolismABSTRACT
Using a customer service paradigm, the authors extended the justification-suppression model (JSM) of prejudice (C. S. Crandall & A. Eshleman, 2003) to include contemporary, covert forms of discrimination and to identify a discrimination remediation mechanism. Overall, the results of 3 studies revealed that actual and confederate obese shoppers in high-prejudice justification conditions faced more interpersonal discrimination than average-weight shoppers. Furthermore, Studies 1 and 2 demonstrate that adopting strategies that remove perceivers' justifications for discriminating against obese individuals (i.e., the controllability of weight) decreases the incidence of interpersonal discrimination. Additionally, Study 3 demonstrates negative bottom-line consequences of interpersonal discrimination for organizations (e.g., customer loyalty, purchasing behavior). Together, these studies confirm that the JSM applies to covert forms of discrimination, show the importance of examining subtle discrimination, and offer a mechanism for theory-driven strategies for the reduction of covert forms of discrimination.
Subject(s)
Interpersonal Relations , Obesity/psychology , Prejudice , Stereotyping , Adult , Cross-Over Studies , Female , Humans , Male , Surveys and QuestionnairesABSTRACT
How do the risks and benefits of nanotechnology, as viewed by the public, compare with those associated with other technologies such as genetically modified organisms, stem cells, biotechnology and nuclear power? And when deciding to use a specific nanotechnology product, will consumers consider the risks, the benefits, or both? We report the first large-scale empirical analyses of these questions.
