Impact of the Siena College Tech Valley Scholars Program on Student Outcomes

The experimental group for this study included 38 students who entered the Tech Valley Scholars (TVS) program over the course of three academic years, from 2009-10 through 2011-12. Two groups of controls were used: a randomly selected sample of STEM students who matriculated in the same time frame; and a matched sample. The TVS students and controls were compared on two primary outcome variables: graduation (or retention to senior year), and final cumulative GPA. The major findings of this study are that (1) the TVS students had better outcomes than both the randomly selected comparison group and the matched control group, (2) unmet financial need is an important risk factor for non-retention, (3) students with moderately high unmet need can be academically successful if retained, and (4) the TVS program is having a positive impact on at-risk students. Recommendations for effective and efficient allocation of scholarship funds are given and future statistical studies are recommended

Nuclear protein import in permeabilized mammalian cells requires soluble cytoplasmic factors

Abstract. We have developed an in vitro system involving digitonin-permeabilized vertebrate cells to study biochemical events in the transport of macromolecules across the nuclear envelope. While treatment of cultured cells with digitonin permeabilizes the plasma membranes to macromolecules, the nuclear envelopes remain structurally intact and nuclei retain the ability to transport and accumulate proteins containing the SV40 large T antigen nuclear location sequence. Transport requires addition of exogenous cytosol to permeabilized cells, indicating the soluble cytoplasmic factor(s) required for nuclear import are released during digitonin treatment. In this reconstituted import system, a protein containing a nuclear location signal is rapidly accumulated in nuclei, wher

The Open Question of How GPCRs Interact with GPCR Kinases (GRKs)

G protein-coupled receptors (GPCRs), which regulate a vast number of eukaryotic processes, are desensitized by various mechanisms but, most importantly, by the GPCR kinases (GRKs). Ever since GRKs were first identified, investigators have sought to determine which structural features of GRKs are used to select for the agonist-bound states of GPCRs and how this binding event in turn enhances GRK catalytic activity. Despite a wealth of molecular information from high-resolution crystal structures of GRKs, the mechanisms driving activation have remained elusive, in part because the GRK N-terminus and active site tether region, previously proposed to serve as a receptor docking site and to be key to kinase domain closure, are often disordered or adopt inconsistent conformations. However, two recent studies have implicated other regions of GRKs as being involved in direct interactions with active GPCRs. Atomic resolution structures of GPCR–GRK complexes would help refine these models but are, so far, lacking. Here, we assess three distinct models for how GRKs recognize activated GPCRs, discuss limitations in the approaches used to generate them, and then experimentally test a hypothetical GPCR interaction site in GRK2 suggested by the two newest models