Microsatellite diversity and genetic structure among common bean (Phaseolus vulgaris L.) landraces in Brazil, a secondary center of diversity

Brazil is the largest producer and consumer of common bean (Phaseolus vulgaris L.), which is the most important source of human dietary protein in that country. This study assessed the genetic diversity and the structure of a sample of 279 geo-referenced common bean landraces from Brazil, using molecular markers. Sixty-seven microsatellite markers spread over the 11 linkage groups of the common bean genome, as well as Phaseolin, PvTFL1y, APA and four SCAR markers were used. As expected, the sample showed lower genetic diversity compared to the diversity in the primary center of diversification. Andean and Mesoamerican gene pools were both present but the latter gene pool was four times more frequent than the former. The two gene pools could be clearly distinguished; limited admixture was observed between these groups. The Mesoamerican group consisted of two sub-populations, with a high level of admixture between them leading to a large proportion of stabilized hybrids not observed in the centers of domestication. Thus, Brazil can be considered a secondary center of diversification of common bean. A high degree of genome-wide multilocus associations even among unlinked loci was observed, confirming the high level of structure in the sample and suggesting that association mapping should be conducted in separate Andean and Mesoamerican Brazilian samples

Musa itinerans var. chiumei (Musaceae), A New Addition to the Taiwan Flora

Another new variety of Musa itinerans Cheesman in Taiwan is described. The morphological characteristics of the variety are otherwise similar to those of var. formosana (Warb. ex Schum.) Halddnen & C.-L.Yeh. The principal distinction is based on the length and bending of inflorescence, and the compactness of fruit hands. The inflorescence rachis of the new variety is longer than the other two varieties, and first upwardly slanting, then curving downwards, finally pendent in the male flower regions. The fruit hands grow very compactly and apex of fruit remains distinguished floral relicts. These characteristics are stable at their habitat and Taiwan Agricultural Research Institute (TART) repository over study periods. This population is herein segregated as the new variety, M. itinerans var. chiumei H.-L. Chiu, C.-T. Shii & T.-Y.A. Yang. Photos for the varietal taxon as well as the key to all variation of Musa itinerans and Taiwanese wild bananas are provided

Musa × formobisiana (Musaceae), a new interspecific hybrid Banana

Taiwan is near the northern limit of distribution of Musaceae. To understand the genetics and extent of genetic diversity in wild bananas in Taiwan, artificial hybrids between Musa itinerans var. formosana and M. balbisiana Colla, here named Musa × formobisiana H.-L. Chiu, C.-T. Shii & T.-Y.A. Yang hybrid nov., were produced. Photos and a comparison of the characteristics of Musa × formobisiana with the parent species are provided. Voucher specimens are at the Herbarium, National Museum of Natural Science, Taiwan (TNM)

Musa itinerans var. chiumei (Musaceae), A New Addition to the Taiwan Flora

Another new variety of Musa itinerans Cheesman in Taiwan is described. The morphological characteristics of the variety are otherwise similar to those of var. formosana (Warb. ex Schum.) Häkkinen & C.-L.Yeh. The principal distinction is based on the length and bending of inflorescence, and the compactness of fruit hands. The inflorescence rachis of the new variety is longer than the other two varieties, and first upwardly slanting, then curving downwards, finally pendent in the male flower regions. The fruit hands grow very compactly and apex of fruit remains distinguished floral relicts. These characteristics are stable at their habitat and Taiwan Agricultural Research Institute (TARI) repository over study periods. This population is herein segregated as the new variety, M. itinerans var. chiumei H.-L. Chiu, C.-T. Shii & T.-Y.A. Yang. Photos for the varietal taxon as well as the key to all variation of Musa itinerans and Taiwanese wild bananas are provided

Musa x formobisiana (Musaceae), a new interspecific hybrid Banana

Taiwan is near the northern limit of distribution of Musaceae. To understand the genetics and extent of genetic diversity in wild bananas in Taiwan, artificial hybrids between Musa itinerans var. formosana and M. balbisiana Colla, here named Musa x formobisiana H.-L. Chiu, C.-T. Shii & T.-Y.A. Yang hybrid nov., were produced. Photos and a comparison of the characteristics of Musa x formobisiana with the parent species are provided. Voucher specimens are at the Herbarium, National Museum of Natural Science, Taiwan (TNM)

Tyrosine phosphorylation of p62(Dok) induced by cell adhesion and insulin: possible role in cell migration.

Dok, a 62-kDa Ras GTPase-activating protein (rasGAP)-associated phosphotyrosyl protein, is thought to act as a multiple docking protein downstream of receptor or non-receptor tyrosine kinases. Cell adhesion to extracellular matrix proteins induced marked tyrosine phosphorylation of Dok. This adhesion-dependent phosphorylation of Dok was mediated, at least in part, by Src family tyrosine kinases. The maximal insulin-induced tyrosine phosphorylation of Dok required a Src family kinase. A mutant Dok (DokDeltaPH) that lacked its pleckstrin homology domain failed to undergo tyrosine phosphorylation in response to cell adhesion or insulin. Furthermore, unlike the wild-type protein, DokDeltaPH did not localize to subcellular membrane components. Insulin promoted the association of tyrosine-phosphorylated Dok with the adapter protein NCK and rasGAP. In contrast, a mutant Dok (DokY361F), in which Tyr361 was replaced by phenylalanine, failed to bind NCK but partially retained the ability to bind rasGAP in response to insulin. Overexpression of wild-type Dok, but not that of DokDeltaPH or DokY361F, enhanced the cell migratory response to insulin without affecting insulin activation of mitogen-activated protein kinase. These results identify Dok as a signal transducer that potentially links, through its interaction with NCK or rasGAP, cell adhesion and insulin receptors to the machinery that controls cell motility