Words similar to activin
Example sentences for: activin
How can you use “activin” in a sentence? Here are some example sentences to help you improve your vocabulary:
BMPs inhibit cell proliferation via downstream Smad1/5/8 proteins whereas Smad7 inhibits TGF-β and activin signaling (Fig.
For example, follistatin binds both activin and BMP-7 avidly but competes weakly or not at all with the type I receptor for BMP-4 binding [ 25 45 ] , whereas noggin binds to BMPs -2 and -4 with greater affinity than BMP-7 [ 46 ] . Whether BMP-5 function can be antagonized by noggin or follistatin has not been previously reported, but our results suggest that simultaneous addition of either antagonist with BMP-5 significantly inhibits the dendrite-promoting activity of BMP-5 in a concentration-dependent manner.
BMPs activate Smad-1 by binding to type I and type II serine-threonine kinase receptors [ 40 41 ] . Specific receptor subunits shown to bind BMPs include BMP receptor type IA (BMPR-IA), BMPR-IB, BMR-II, activin receptor type I (ActR-I), and ActR-II [ 42 43 44 ] . BMP ligands can bind to either type I or type II receptor subunits independently, but both receptor types are required for high-affinity binding and signaling [ 40 ] . The finding that the soluble BMPR-IA-Fc chimera significantly inhibits BMP-5 induced dendritic growth suggests that BMP-5 may be activating the Smad-1 signaling pathway via interactions with BMPR-IA.
This inhibition of TGF-β/activin signaling is modulated through NF-κB-dependent inhibition of Smad7 [ 40 ] . In addition, there is a negative feedback between NF-κB and Smad7; activated NF-κB inhibits Smad7 promotor activity [ 41 ] whereas Smad7 inhibits NF-κB activation and potentiates apoptosis [ 42 ] . Curiously, the relative importance of increased Smad7 expression is 20 times greater than that of Smad1/5
These data are consistent with conclusions from previous studies indicating that dendrite-promoting activity is restricted to BMPs from the 60A or dpp (BMPs 2 and 4) subgroups and is not observed with BMPs from other subgroups such as BMP-3, BMP-13 or dorsalin, or with other members of the TGF-β superfamily such as activin, TGF-β1, -β2 or -β3 [ 16 17 ] . Functional redundancy between BMPs of the 60A subgroup has been previously reported with respect to other developmental endpoints [ 6 ] , of which some, such as upregulation of cell adhesion molecules [ 30 ] , may be directly relevant to effects on dendritic growth.
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