Conversion of active GTP-bound Ras to its inactive GDP-bound form is catalyzed by GTPase-activating proteins (GAPs). Two mammalian
Ras-specific GAPs, p120GAP and neurofibromin, the product of the NF1 ...tumor suppressor gene, have been previously described.
We report here the identification of a new human cDNA clone, IQGAP1, which predicts a 1657-amino acid protein that displays
extensive sequence similarity to the catalytic domain of all previously reported RasGAPs. IQGAP1 is most closely related to
the Schizosaccharomyces pombe RasGAP-like protein, Sar1. Sequence similarity to IQGAP1 is seen throughout the entire Sar1
protein. The N-terminal half of IQGAP1, which does not overlap with Sar1, contains six copies of a unique amino acid motif,
as well as four so-called IQ motifs. The latter motifs are found in several proteins, including conventional and unconventional
myosins, and mediate the interaction with calmodulin and calmodulin-related proteins. Thus, IQGAP1 appears to represent a
novel RasGAP-like protein that may link Ras signaling to some calmodulin-mediated process.
A very cool brown dwarf in UKIDSS DR1 Warren, S. J.; Mortlock, D. J.; Leggett, S. K. ...
Monthly notices of the Royal Astronomical Society,
11/2007, Volume:
381, Issue:
4
Journal Article
A major research limitation in investigating the validity of the TAIS has been the failure to distinguish when attentional style has an effect on the information processing system, early as in ...encoding or late after processing. Few investigations have examined the TAIS predictive validity in a controlled setting wherein task attention demands can be systematically and accurately varied. Does the general trait of attentional style really have anything to do with
how
attention related information is processed? The present study examined this question using a valid attention theory (Treisman's feature integration theory) and a visual search paradigm. When the TAIS attentional-style scales were correlated with visual search rate for attention demanding targets, no significant relationships were observed. Specifically, TAIS scales did not relate to visual search rate for an attention demanding target, the performance of subjects extreme in search rate, or the central to peripheral slowing of search time in target detection. The factorial validity of the TAIS was also questioned. It was concluded that the attentional-style scales were not valid in predicting how attention related visual information is processed. The importance of distinguishing when attentional style might be operating in the information processing system was emphasized for future research.
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