Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A single-stranded DNA probe complementary to chicken type II procollagen mRNA has been used to quantitate levels of that mRNA present in chicken limb mesenchyme during cartilage differentiation. Excess labeled probe prepared from a cDNA template cloned in M13mp9 was hybridized to completion to increasing amounts of total RNA and assayed by protection from S1 nuclease digestion. Estimates of the absolute levels of type II procollagen RNA were determined using the M13mp9 template containing the coding strand as a standard. RNA complementary to the probe increased from 20 copies per diploid genome in stage 24 limb to approximately 2000 copies per diploid genome in stage 24 limb mesenchyme which had differentiated to cartilage in culture. Similar levels were found in cartilage from stage 31 limb. Sternal cartilage from 17-day embryos contained approximately 10,000 copies per diploid genome suggesting that the level of expression of this gene is different in limb growth cartilage compared with sternal cartilage. Low but detectable levels of RNA complementary to the probe were observed in limb at stages 20-24. Since a large fraction of the type II procollagen RNA in these early limbs is associated with polysomes, the type II procollagen gene appears to be expressed at a low level prior to phenotypic differentiation and prior to the accumulation of immunologically detectable levels of type II collagen.
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PMID:Quantitation of type II procollagen mRNA levels during chick limb cartilage differentiation. 383 85

Transforming growth factor (TGF)-beta has an essential role for the Sry-type high-mobility-group box (Sox)-regulated chondrogenesis. Chondrogenic differentiation is also controlled by chromatin-mediated transcription. We have previously reported that TGF-beta-regulated Smad3 induces chondrogenesis through the activation of Sox9-dependent transcription. However, the cross-talk between TGF-beta signal and Sox9 on chromatin-mediated transcription has not been elucidated. In the present study, we investigated the activity of Smad3, Sox9, and coactivator p300 using an in vitro chromatin assembly model. Luciferase reporter assays revealed that Smad3 stimulated the Sox9-mediated transcription in a TGF-beta-dependent manner. Recombinant Sox9 associated with phosphorylated Smad3/4 and recognized the enhancer region of type II collagen gene. In vitro transcription and S1 nuclease assays showed that Smad3 and p300 cooperatively activated the Sox9-dependent transcription on chromatin template. The combination treatment of phosphorylated Smad3, Sox9, and p300 were necessary for the activation of chromatin-mediated transcription. These findings suggest that TGF-beta signal Smad3 plays a key role for chromatin remodeling to induce chondrogenesis via its association with Sox9.
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PMID:Smad3 activates the Sox9-dependent transcription on chromatin. 1904 14