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Misra, JR, Irvine KD.  2016.  Vamana Couples Fat Signaling to the Hippo Pathway.. Developmental cell. 39(2):254-266. Abstract
The protocadherins Dachsous and Fat initiate a signaling pathway that controls growth and planar cell polarity by regulating the membrane localization of the atypical myosin Dachs. How Dachs is regulated by Fat signaling has remained unclear. Here we identify the vamana gene as playing a crucial role in regulating membrane localization of Dachs and in linking Fat and Dachsous to Dachs regulation. Vamana, an SH3-domain-containing protein, physically associates with and co-localizes with Dachs and promotes its membrane localization. Vamana also associates with the Dachsous intracellular domain and with a region of the Fat intracellular domain that is essential for controlling Hippo signaling and levels of Dachs. Epistasis experiments, structure-function analysis, and physical interaction experiments argue that Fat negatively regulates Dachs in a Vamana-dependent process. Our findings establish Vamana as a crucial component of the Dachsous-Fat pathway that transmits Fat signaling by regulating Dachs.
Hawkins, JS, Delgado V, Feng L, Carlise M, Dooner HK, Bennetzen JL.  2014.  Variation in allelic expression associated with a recombination hotspot in Zea mays.. The Plant Journal, DOI: 10.1111/tpj.12537. Abstract
Gene expression is a complex process, requiring precise spatial and temporal regulation of transcription factor activity; however, modifications of individual cis- and trans-acting modules can be molded by natural selection to create a sizeable number of novel phenotypes. Results from decades of research indicate that developmental and phenotypic divergence among eukaryotic organisms is driven primarily by variation in levels of gene expression that are dictated by mutations either in structural or regulatory regions of genes. The relative contributions and interplay of cis- and trans-acting regulatory factors to this evolutionary process, however, remain poorly understood. Analysis of 8 genes in the Bz1-Sh1 interval of maize indicates significant allele-specific expression biases in at least one tissue for all genes, ranging from 1.3-fold to 36-fold. All detected effects were cis-regulatory in nature, although genetic background may also influence the level of expression bias and tissue specificity for some allelic combinations. Most allelic pairs exhibited the same direction and approximate intensity of bias across all four tissues; however, a subset of allelic pairs show alternating dominance across different tissue types or variation in the degree of bias in different tissues. In addition, the genes showing the most striking levels of allelic bias co-localize with a previously described recombination hotspot in this region, suggesting a naturally occurring genetic mechanism for creating regulatory variability for a subset of plant genes that may ultimately lead to evolutionary diversification.
Das, OP, Messing J.  1994.  Variegated phenotype and developmental methylation changes of a maize allele originating from epimutation. Genetics. 136:1121-41. AbstractWebsite
Two instances of genetic transmission of spontaneous epimutation of the maize P-rr gene were identified. Transmission gave rise to two similar, moderately stable alleles, designated P-pr-1 and P-pr-2, that exhibited Mendelian behavior. Both isolates of P-pr conditioned a variable and variegated phenotype, unlike the uniform pigmentation conditioned by P-rr. Extensive genomic analysis failed to reveal insertions, deletions or restriction site polymorphisms between the new allele and its progenitor. However, methylation of the P gene was increased in P-pr relative to P-rr, and was greatly reduced (though not lost) in a revertant to uniform pigmentation. Variability in pigmentation conditioned by P-pr correlated with variability in transcript levels of the P gene, and both correlated inversely with variability in its methylation. Part of the variability in methylation could be accounted for by a developmental decrease in methylation in all tissues of plants carrying P-pr. We hypothesize that the variegated phenotype results from a general epigenetic pathway which causes a progressive decrease in methylation and increase in expression potential of the P gene as a function of cell divisions in each meristem of the plant. This renders all tissues chimeric for a functional gene; chimerism is visualized as variegation only in pericarp due to the tissue specificity of P gene expression. Therefore, this allele that originates from epimutation may exemplify an epigenetic mechanism for variegation in maize.
Heidecker, G, Messing J, Gronenborn B.  1980.  A versatile primer for DNA sequencing in the M13mp2 cloning system. Gene. 10:69-73. AbstractWebsite
A primer for DNA sequencing by the chain-termination method in the M13mp2 cloning system was constructed and amplified. The primer was isolated as an EcoRI/AluI restriction fragment. After conversion of the AluI end into an EcoRI end the fragment was cloned in pBR325 from which it can be recovered by cleavage with EcoRI. The primer hybridizes to the single-stranded DNA of the mature M13mp2 phage next to the site of insertion thereby directing DNA synthesis along the inserted DNA.
Wu, XR, Chen Z, Shende A, Dooner HK, Folk WR.  2006.  Visualizing bz1 missense suppression in Zea mays: an assay for monocot tRNA expression and utilization. Plant Mol. Biol.. 61:795–798. Abstract
Val missense mutation, visualized by the development of anthocyanin pigment. Missense suppression is blocked by mutation of tRNA(ala)(GAC) at a site that prevents aminoacylation by the dicot alanyl-tRNA synthetase, indicating that features identified for expression and utilization of dicot tRNAs also function in monocots. This assay of the expression and utilization of tRNA(ala)(GAC) also can be used to study a variety of tRNAs and their genes, most of which can be relatively easily altered to be charged by alanyl tRNA synthetase.