Sonic hedgehog (Shh), a vertebrate homologue of the Drosophila segment polarity gene Hedgehog, is required for patterning in the developing central nervous system, somite, and limb. It is produced as a 47-49 kDa secreted holoprotein that is autocatalytically cleaved to yield a 19 kDa N-terminal
A morphogen is classically defined as a signaling molecule that elicits different cellular responses depending on its concentration. More specifically, morphogens are secreted molecules that drive the organization of regional groups of cells into patterns. The absolute concentration of the
During development of the nervous system, axons at times navigate considerable distances before finally reaching their appropriate targets. The highly motile growth cone at the tip of an extending axon is exquisitely sensitive to attractive and repellent cues in the extracellular environment. These
First printed in R&D Systems' 2002 catalog. Contents Introduction Ligands Distribution Structure Function Conclusion References Introduction Natural killer (NK) cells are an important element of the innate immune system as they are capable of killing tumor cells and virally-infected cells.
Exceptional Performance at the Best Value R&D Systems understands that researchers require large quantities of purified cytokines and growth factors for cell culture. In an effort to provide the best value to researchers, several of the most widely used proteins are now being offered at new
The future utilization of stem cell therapy for neurodegenerative disease has been impeded by the limited numbers of stem cells that can be generated in vitro for transplantation, the potential immune response to the transplanted cells, and the sparse population of endogenous progenitor cells that
Introduction to Cancer Stem Cells Cancer stem cells (CSCs) are classically described as a tumor cell subpopulation that is multipotent, oncogenic, and capable of self-renewal. 1, 2 They may serve as an ongoing source for differentiating tumor cells and can exhibit characteristics that confer