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Betaglycan (T?RIII) is a Key Factor in TGF-?2 Signaling in Prepubertal Rat Sertoli Cells.

ABSTRACT: Transforming growth factor-?s (TGF-?s) signal after binding to the TGF-? receptors T?RI and T?RII. Recently, however, betaglycan (BG) was identified as an important co-receptor, especially for TGF-?2. Both proteins are involved in several testicular functions. Thus, we analyzed the importance of BG for TGF-?1/2 signaling in Sertoli cells with ELISAs, qRT-PCR, siRNA silencing and BrdU assays. TGF-?1 as well as TGF-?2 reduced shedding of membrane-bound BG (mBG), thus reducing the amount of soluble BG (sBG), which is often an antagonist to TGF-? signaling. Treatment of Sertoli cells with GM6001, a matrix metalloproteinases (MMP) inhibitor, also counteracted BG shedding, thus suggesting MMPs to be mainly involved in shedding. Interestingly, TGF-?2 but not TGF-?1 enhanced secretion of tissue inhibitor of metalloproteinases 3 (TIMP3), a potent inhibitor of MMPs. Furthermore, recombinant TIMP3 attenuated BG shedding. Co-stimulation with TIMP3 and TGF-?1 reduced phosphorylation of Smad3, while a combination of TIMP3/TGF-?2 increased it. Silencing of BG as well as TIMP3 reduced TGF-?2-induced phosphorylation of Smad2 and Smad3 significantly, once more highlighting the importance of BG for TGF-?2 signaling. In contrast, this effect was not observed with TIMP3/TGF-?1. Silencing of BG and TIMP3 decreased significantly Sertoli cell proliferation. Taken together, BG shedding serves a major role in TGF-?2 signaling in Sertoli cells.

SUBMITTER: Kudipudi PK

PROVIDER: S-EPMC6941059 | biostudies-literature | 2019 Dec

REPOSITORIES: biostudies-literature

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Betaglycan (TβRIII) is a Key Factor in TGF-β2 Signaling in Prepubertal Rat Sertoli Cells.

Kudipudi Pradeep K PK Galuska Sebastian P SP Dietze Raimund R Scheiner-Bobis Georgios G Loveland Kate L KL Konrad Lutz L

International journal of molecular sciences 20191209 24

Transforming growth factor-βs (TGF-βs) signal after binding to the TGF-β receptors TβRI and TβRII. Recently, however, betaglycan (BG) was identified as an important co-receptor, especially for TGF-β2. Both proteins are involved in several testicular functions. Thus, we analyzed the importance of BG for TGF-β1/2 signaling in Sertoli cells with ELISAs, qRT-PCR, siRNA silencing and BrdU assays. TGF-β1 as well as TGF-β2 reduced shedding of membrane-bound BG (mBG), thus reducing the amount of soluble ...[more]

PMID: 31835434

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Dataset Information

Betaglycan (T?RIII) is a Key Factor in TGF-?2 Signaling in Prepubertal Rat Sertoli Cells.

Publications

Betaglycan (TβRIII) is a Key Factor in TGF-β2 Signaling in Prepubertal Rat Sertoli Cells.

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