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C T Payne

Publications and source records attributed to C T Payne.

4 recordsLinked to original sources
PubMed2000

GL3 encodes a bHLH protein that regulates trichome development in arabidopsis through interaction with GL1 and TTG1.

Arabidopsis trichome development and differentiation is a well-studied model for plant cell-fate determination and morphogenesis. Mutations in TRANSPARENT TESTA GLABRA1 (TTG1) result in several pleiotropic defects including an almost complete lack of trichomes. The complex phenotype caused by ttg1 mutations is suppressed by ectopic expression of the maize anthocyanin regulator R. Here it is demonstrated that the Arabidopsis trichome development locus GLABRA3 (GL3) encodes an R homolog. GL3 and GLABRA1 (GL1) interact when overexpressed together in plants. Yeast two-hybrid assays indicate that GL3 participates in physical interactions with GL1, TTG1, and itself, but that GL1 and TTG1 do not interact. These data suggest a reiterated combinatorial model for the differential regulation of such diverse developmental pathways as trichome cell-fate determination, root hair spacing, and anthocyanin secondary metabolism.

Amino Acid Sequence↗
PubMedDate not supplied

Genomic distribution of heterochromatic sequences in equids: implications to rapid chromosomal evolution.

We describe a molecular model for rapid chromosomal evolution that proposes tandemly repeated DNA sequences as a driving force. A prediction of this model is that when extensive rearrangements of euchromatin have been facilitated by heterochromatin, genomes will be characterized by tandemly repeated sequences that have actively changed chromosomal fields by intragenomic movement. Alternatively, it is proposed that in conservative chromosomal lineage each class of tandemly repeated sequences will be restricted to a specific chromosomal field. To provide baseline data to test this model we examined four classes of tandemly repeated elements in six species of equids (Equus). Distribution of these sequences among species, as determined from slot blot analysis, and restriction site variation, shown by Southern blot hybridization, document that these sequences are in an evolutionarily dynamic state, and in situ hybridization documents extensive intragenomic movement among nonhomologous chromosomes and chromosomal fields. These data are interpreted as being compatible with the predictions of this model. Although this is clearly not the sole molecular factor driving chromosomal evolution, the model appears to be viable as an explanation of certain patterns of chromosomal evolution such as karyotypic megaevolution and some types of karyotypic orthoselection.

Animals↗