The subgenus is an obligate forest and stream-dwelling group of mantellid frogs, endemic to Madagascar, with six species currently recognized. However, this group suffers from ongoing taxonomic confusion due to low numbers of examined specimens, and failure to consider morphological variation from development and sexual dimorphism. Here, we examined the morphology of 637 sexed adult specimens collected by us in the field and from other museum collections.
View Article and Find Full Text PDFMol Phylogenet Evol
February 2022
Lizards of the clade Iguanidae (sensu lato) are primarily a New World group. Thus, the remarkable presence of an endemic lineage of iguanas (family Opluridae) on the isolated Indian Ocean island of Madagascar has long been considered a biogeographic anomaly. Previous work attributed this disjunct extant distribution to: (1) vicariance at about 140-165 Ma, caused by the breakup of Gondwana and the separation of South America, Africa, and Madagascar (with subsequent extinction of iguanas on Africa, and potentially other Gondwanan landmasses), (2) vicariance at about 80-90 Ma, caused by the sundering of hypothesized land-bridge connections between South America, Antarctica, India, and Madagascar, or (3) long-distance overwater dispersal from South America to Madagascar.
View Article and Find Full Text PDFThe concept that the B-cell Receptor (BCR) initiates a driver pathway in lymphoma-leukemia has been clinically validated. Previously described unique BCR Ig-class-specific sequences (proximal domains (PDs)), are not expressed in serum Ig (sIg). As a consequence of sequence and structural differences in the membrane IgM (mIgM) µ-Constant Domain 4, additional epitopes distinguish mIgM from sIgM.
View Article and Find Full Text PDFThe impact of environmental change on population structure is not well understood. This study aimed to examine the effect of a climate change event on gene flow over space and time in two populations of Brassica rapa that evolved more synchronous flowering times over 5 years of drought in southern California. Using plants grown from seeds collected before and after the drought, we estimated genetic parameters within and between populations and across generations.
View Article and Find Full Text PDFCell surface transmembrane signaling receptors EGFR, HER3, and HER4 are activated by ligand-binding-mediated dimerization and phosphorylation. In contrast, HER2 amplification promotes signaling by increasing homo/heterodimerization and ligand binding. Trastuzumab or lapatinib therapy of HER2 amplicon-positive breast cancer cells induces growth inhibition and intracellular growth pathway signaling modulation.
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