English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Activins and transforming growth factor-beta (TGF beta) are crucial autocrine, paracrine, and endocrine modulators of anterior pituitary function. Activins regulate most pituitary cells and lactotropes are targets of TGF beta. Smad2 and Smad3 are two cellular mediators of activin/TGF beta signaling, whereas Smad7 is as an inducible, negative modulator of the pathway. This study was undertaken to evaluate Smad7 regulation in the pituitary. Activin A rapidly and transiently increased Smad7 messenger RNA (mRNA) levels of rat anterior pituitary (RAP), clonal gonadotrope (alpha T 3-1 and L beta T2), and corticotrope (AtT20) cells with an EC(50) of 0.1-0.2 nM. In RAP cells, activin A or TGF beta 1 had equivalent effects that were additive. Follistatin, known to bind and inactivate activins, prevented Smad7 induction by activin. Inhibin A partially antagonized activin A, perhaps reflecting gonadotrope-selective actions. This antagonism was also evident with alpha T 3-1 and L beta T2 gonadotropes. Forskolin had no measurable effect in RAP cells, but increased Smad7 mRNA levels in alpha T3-1 cells and decreased them in L beta T2 cells. Transient transfection of Smad7 along with 3TPLux, an activin/TGF beta-responsive reporter, blocked activin-mediated promoter activation in alpha T3-1 and AtT20 cells. In alpha T3-1 cells, which express endogenous follistatin mRNA, a follistatin-luciferase reporter, rFS(rin3)-Luc, was transcriptionally activated by activin A, or when cotransfected with a constitutively active ActRIB [Alk4(T&gt;D)], Smad2, or Smad3. Smad7 blocked rFS(rin3)-Luc activation by activin A or Alk4(T&gt;D). Together, these results point to a role of Smad7 in modulating activin/TGF beta signaling in the pituitary.

endocrinology

Regulation and Actions of Smad7 in the Modulation of Activin, Inhibin, and Transforming Growth Factor-β Signaling in Anterior Pituitary Cells<sup>1</sup>

Regulation and Actions of Smad7 in the Modulation of Activin, Inhibin, and Transforming Growth Factor-β Signaling in Anterior Pituitary Cells1

Regulation and Actions of Smad7 in the Modulation of Activin, Inhibin, and Transforming Growth Factor-β Signaling in Anterior Pituitary Cells¹