Synthesis and photophysical characterization of fluorescent indole nucleoside analogues.

Fluorescent nucleosides are useful chemical tools for biochemical research and are frequently incorporated into nucleic acids for a variety of applications. The most widely utilized fluorescent nucleoside is 2-aminopurine-2'-deoxyribonucleoside (2APN). However, 2APN is limited by a moderate Stokes shift, molar extinction coefficient, and quantum yield.

Exocrine ontogenies: on the development of pancreatic acinar, ductal and centroacinar cells.

This review summarizes our current understanding of exocrine pancreas development, including the formation of acinar, ductal and centroacinar cells. We discuss the transcription factors associated with various stages of exocrine differentiation, from multipotent progenitor cells to fully differentiated acinar and ductal cells. Within the branching epithelial tree of the embryonic pancreas, this involves the progressive restriction of multipotent pancreatic progenitor cells to either a central "trunk" domain giving rise to the islet and ductal lineages, or a peripheral "tip" domain giving rise to acinar cells.

Overcoming redundancy: an RNAi enhancer screen for morphogenesis genes in Caenorhabditis elegans.

Morphogenesis is an important component of animal development. Genetic redundancy has been proposed to be common among morphogenesis genes, posing a challenge to the genetic dissection of morphogenesis mechanisms. Genetic redundancy is more generally a challenge in biology, as large proportions of the genes in diverse organisms have no apparent loss of function phenotypes.

Apical constriction: a cell shape change that can drive morphogenesis.

Biologists have long recognized that dramatic bending of a cell sheet may be driven by even modest shrinking of the apical sides of cells. Cell shape changes and tissue movements like these are at the core of many of the morphogenetic movements that shape animal form during development, driving processes such as gastrulation, tube formation, and neurulation. The mechanisms of such cell shape changes must integrate developmental patterning information in order to spatially and temporally control force production-issues that touch on fundamental aspects of both cell and developmental biology and on birth defects research.

Analysis of novel and recurrent mutations responsible for the tricho-rhino-phalangeal syndromes.

The tricho-rhino-phalangeal syndromes (TRPS type I, II, and III) are autosomal dominant disorders sharing the following characteristics: slowly growing and sparse scalp hair, medially thick and laterally thin eyebrows, bulbous tip of the nose, long flat philtrum, thin upper lip with vermilion border, and protruding ears. In addition, individuals with TRPS generally share skeletal and bone anomalies, including shortening of the phalanges and metacarpals (mild to severe brachydactyly), cone-shaped epiphyses, hip dysplasia, and short stature. The etiology of the different types of TRPS can result from either single base pair mutations, or the complete deletion of the TRPS1 gene, which encodes a zinc-finger transcription factor located on chromosomal band 8q24.