Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10721 (c-kit)
 6,575 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have been studying hematopoietic effects by the tachykinins, which like many other neuropeptides can be expressed in neural and nonneural tissues. Substance P (SP) and neurokinin-A (NK-A), members of the tachykinins are immune and hematopoietic modulators. SP and NK-A are derived from the preprotachykinin-I gene (PPT-I) through alternate splicing and posttranslational modification. In the bone marrow (BM), nerve fibers provide a source of neural SP and the stroma provides a source of nonneural SP. The tachykinins interact with each of three cloned neurokinin (NK) receptors (NK-1R, NK-2R, NK-3R) with SP and NK-A exhibiting binding preferences for NK-1R and NK-2R, respectively. Proliferation of myeloid progenitors (CFU-GM) is differentially regulated by SP and NK-A. The former enhances the proliferation whereas the latter is inhibitory. The BM stroma mediates most of the hematopoietic effects exerted by SP and NK-A partly through the induction of cytokines. The proliferative effects of SP correlate with the induction of positive hematopoietic growth factors such as IL-3, IL-6, GM-CSF and c-kit ligand and the inhibitory effects by NK-A correlate with the induction of two negative hematopoietic regulators, MIP-1 alpha and TGF-beta. Intracellular signals mediated by NK-1R and NK-2R are part of the mechanism responsible for tachykinin-mediated regulation of hematopoiesis. The stimulatory effects on BM progenitors mediated by NK-1R can be partly inhibited by NK-2R activation. IL-1 and other cytokines induced by SP in BM stroma modulate NK-1R induction. Furthermore, SP can induce IL-1 type I receptor in stroma. Together, these data suggest that the tachykinins and the cytokines interact to regulate hematopoiesis. These interactions contribute to hematopoietic regulation by mechanisms that involve induction of: (1) tachykinins and cytokines by each other; (2) NK-1R by cytokines and (3) cytokine receptor by the tachykinins. These studies emphasize that in terms of hematopoiesis, the cytokines and neuropeptides are not mutually exclusive factors and thus, the hematopoietic regulatory network would be incomplete without the role of neuropeptides being considered.
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PMID:Hematopoietic modulation by the tachykinins. 928

Caveolin (Cav)-1 is an integral membrane protein of caveolae playing a crucial role in various signal transduction pathways. Caveolae represent the sites for calcium entry and storage especially in smooth muscle cells (SMC) and interstitial cells of Cajal (ICC). Cav-1(-/-) mice lack caveolae and show abnormalities in pacing and contractile activity of the small intestine. Presently, we investigated, by transmission electron microscopy (TEM) and immunohistochemistry, whether the absence of Cav-1 in Cav-1(-/-) mouse small intestine affects ICC, SMC and neuronal morphology, the expression of NK1 and NK2 receptors, and of Ano1 (also called Dog1 or TMEM16A), an essential molecule for slow wave activity in gastrointestinal muscles. ICC were also labelled with c-Kit and tachykinergic neurons with Substance P (SP). In Cav-1(-/-) mice: (i) ICC were Ano1-negative but maintained c-Kit expression, (ii) NK1 and NK2 receptor immunoreactivity was more intense and, in the SMC, mainly intracytoplasmatic, (iii) SP-immunoreactivity was significantly reduced. Under TEM: (i) ICC, SMC and telocytes lacked typical caveolae but had few and large flask-shaped vesicles we called large-sized caveolae; (ii) SMC and ICC contained an extraordinary high number of mitochondria, (iii) neurons were unchanged. To maintain intestinal motility, loss of caveolae and reduced calcium availability in Cav-1-knockout mice seem to be balanced by a highly increased number of mitochondria in ICC and SMC. Loss of Ano-1 expression, decrease of SP content and consequently overexpression of NK receptors suggest that all these molecules are Cav-1-associated proteins.
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PMID:NK receptors, Substance P, Ano1 expression and ultrastructural features of the muscle coat in Cav-1(-/-) mouse ileum. 2153 98