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This cross-sectional survey explored the association between functional health literacy and knowledge of, beliefs and attitudes about, and reported usage of colorectal cancer screening tests. The results indicate that functional health literacy, as assessed by the Short Test of Functional Health Literacy in Adults (STOFHLA), is not an independent predictor of colorectal cancer screening knowledge, beliefs, attitudes, or behavior. Latino ethnicity and education, however, often predicted screening responses, suggesting that efforts to improve communication about colorectal cancer screening with Latino patients and patients with low education clearly are needed to reduce the disparities in awareness and utilization of colorectal cancer screening tests. This study also explored influences on intended screening behavior. Physician recommendation was found to be a powerful motivator of intention to undergo colorectal cancer screening regardless of literacy level, indicating that interventions aimed at increasing physician recommendation of colorectal cancer screening may be an effective way of increasing screening rates.

The yeast vacuole functions both as a degradative organelle and as a storage depot for small molecules and ions. Vacuoles are dynamic reticular structures that appear to alternately fuse and fragment as a function of growth stage and environment. Vac8p, an armadillo repeat-containing protein, has previously been shown to function both in vacuolar inheritance and in protein targeting from the cytoplasm to the vacuole. Both myristoylation and palmitoylation of Vac8p are required for its efficient localization to the vacuolar membrane (Y.-X. Wang, N. L. Catlett, and L. S. Weisman, J. Cell Biol. 140:1063-1074, 1998). We report that mutants with conditional defects in the rate-limiting enzyme of fatty acid synthesis, acetyl coenzyme A carboxylase (ACC1), display unusually multilobed vacuoles, similar to those observed in vac8 mutant cells. This vacuolar phenotype of acc1 mutant cells was shown biochemically to be accompanied by a reduced acylation of Vac8p which was alleviated by fatty acid supplementation. Consistent with the proposed defect of acc1 mutant cells in acylation of Vac8p, vacuolar membrane localization of Vac8p was impaired upon shifting acc1 mutant cells to nonpermissive condition. The function of Vac8p in protein targeting, on the other hand, was not affected under these conditions. These observations link fatty acid synthesis and availability to direct morphological alterations of an organellar membrane.

In a screen for mutants that display synthetic lethal interaction with hpr1Delta, a hyperrecombination mutant of Saccharomyces cerevisiae, we have isolated a novel cold-sensitive allele of the acetyl coenzyme A (CoA) carboxylase gene, acc1(cs), encoding the rate-limiting enzyme of fatty acid synthesis. The synthetic lethal phenotype of the acc1(cs) hpr1Delta double mutant was only partially complemented by exogenous fatty acids. hpr1Delta was also synthetically lethal with a previously isolated, temperature-sensitive allele of ACC1, mtr7 (mRNA transport), indicating that the lethality of the acc1(cs) hpr1Delta double mutant was not allele specific. The basis for the interaction between conditional acc1 alleles and hpr1Delta was investigated in more detail. In the hpr1Delta mutant background, acetyl-CoA carboxylase enzyme activity was reduced about 15-fold and steady-state levels of biotinylated Acc1p and ACC1 mRNA were reduced 2-fold. The reduced Acc1p activity in hpr1Delta cells, however, did not result in an altered lipid or fatty acid composition of the mutant membranes but rendered cells hypersensitive to soraphen A, an inhibitor of Acc1p. Similar to mtr7, hpr1Delta and acc1(cs) mutant cells displayed a defect in nuclear export of polyadenylated RNA. Oversized transcripts were detected in hpr1Delta, and rRNA processing was disturbed, but pre-mRNA splicing appeared wild type. Surprisingly, the transport defect of hpr1Delta and acc1(cs) mutant cells was accompanied by an altered ring-shaped structure of the nucleolus. These observations suggest that the basis for the synthetic lethal interaction between hpr1Delta and acc1 may lie in a functional overlap of the two mutations in nuclear poly(A)+ RNA production and export that results in an altered structure of the nucleolus.