排序方式: 共有97条查询结果,搜索用时 109 毫秒
91.
Hes1-deficient mice show precocious differentiation of Paneth cells in the small intestine 总被引:4,自引:0,他引:4
Suzuki K Fukui H Kayahara T Sawada M Seno H Hiai H Kageyama R Okano H Chiba T 《Biochemical and biophysical research communications》2005,328(1):348-352
We have previously shown that Hes1 is expressed both in putative epithelial stem cells just above Paneth cells and in the crypt base columnar cells between Paneth cells, while Hes1 is completely absent in Paneth cells. This study was undertaken to clarify the role of Hes1 in Paneth cell differentiation, using Hes1-knockout (KO) newborn (P0) mice. Electron microscopy revealed premature appearance of distinct cells containing cytoplasmic granules in the intervillous region in Hes1-KO P0 mice, whereas those cells were absent in wild-type (WT) P0 mice. In Hes1-KO P0 mice, the gene expressions of cryptdins, exclusively present in Paneth cells, were all enhanced compared with WT P0 mice. Immunohistochemistry demonstrated increased number of both lysozyme-positive and cryptdin-4-positive cells in the small intestinal epithelium of Hes1-KO P0 mice as compared to WT P0 mice. Thus, Hes1 appears to have an inhibitory role in Paneth cell differentiation in the small intestine. 相似文献
92.
His-Asp phosphorelay signaling: a communication avenue between plants and their environment 总被引:5,自引:0,他引:5
His-Asp phosphorelay systems have been recently discovered in plants and have emerged as some of the most important signaling systems. The phosphorelay systems in plants include components with sensor (His-protein kinase) domains, His-containing phosphotransfer (HPt) domains, and receiver (response regulator) domains. Recent studies implicate phosphorelay systems in sensing and propagating signals from a wide variety of external and/or internal stimuli such as ethylene, cytokinin, and osmolarity. In maize and Arabidopsis, some response regulators are up-regulated by both cytokinins and nitrate. These findings imply that the His-Asp phosphorelay may operate in an inorganic nitrogen-signaling pathway mediated by cytokinin in plants. 相似文献
93.
94.
95.
96.
97.
Naosuke Kojima M. Sato Katsuyuki Imai Mitsutaka Miura Yoshikazu Matano Haruki Senoo 《Histochemistry and cell biology》1998,110(2):121-128
When cultured on a polystyrene surface or aminoalkylsilane-coated cover glasses, rat and human hepatic stellate cells exhibit
a flattened, fibroblast-like shape with well-developed stress fibers. However, culturing the cells on type I collagen gel
results in the elongation of long, multipolar cellular processes, whereas cells cultured on Matrigel maintain their round
shapes. Dual fluorescence staining of microtubules and fibrillar actin indicated that the processes extend together with collagen
fibers and contained microtubules as the core, whereas the periphery contained fibrillar actin. Immunofluorescence staining
of vinculin showed that the focal adhesions were distributed mainly in lamellipodia when cultured on aminoalkylsilane-coated
cover glasses, whereas in the cells cultured on type I collagen gel they were localized to the tips of the processes and along
their bottom surface contacting collagen fibers. Wortmannin, as well as staurosporin and herbimycin A, inhibited the elongation
process and induced the retraction of elongated processes. The wortmannin treatment also resulted in an alteration in focal
adhesion distribution from the processes to cell bodies. These results indicate that the cell surface integrin binding to
interstitial collagen fibers induces the elongation of processes through signaling events and the subsequent cytoskeleton
assembly in hepatic stellate cells.
Accepted: 12 February 1998 相似文献