SHANK proteins limit integrin activation by directly interacting with Rap1 and R-Ras.

SHANK3, a synaptic scaffold protein and actin regulator, is widely expressed outside of the central nervous system with predominantly unknown function. Solving the structure of the SHANK3 N-terminal region revealed that the SPN domain is an unexpected Ras-association domain with high affinity for GTP-bound Ras and Rap G-proteins. The role of Rap1 in integrin activation is well established but the mechanisms to antagonize it remain largely unknown.

Establishing minimum performance standards, calibration intervals, and optimal exposure values for a whole breast digital mammography unit.

Methods are developed to establish minimum performance standards, calibration intervals, and criteria for exposure control for a whole breast digital mammography system. A prototype phantom was designed, and an automatic method programmed, to analyze CNR, resolution, and dynamic range between CCD components in the image receptor and over time. The phantom was imaged over a 5 month period and the results are analyzed to predict future performance.

Sequence analysis of the indirect flight muscle actin-encoding gene of Drosophila simulans.

A genomic clone of the Drosophila simulans indirect flight muscle actin-encoding gene (Act88F) has been isolated, and the sequence of a 3358-nucleotide segment corresponding to the Drosophila melanogaster Act88F transcription unit is presented. The ACt88F homologs in these two sibling species encode identical proteins and the general genomic organization of the Act88F locus is highly conserved, including the location of the transcription start point, and the size and position of intron/exon junctions. Substitutions within the 5' flanking region, however, are clearly nonuniform and the regions of lowest divergence coincide with regions that have been implicated in transcript accumulation and the regulation of tissue-specific expression.