TY - JOUR
T1 - GnRH induces ERK-dependent bleb formation in gonadotrope cells, involving recruitment of members of a GnRH receptor-associated signalosome to the blebs
AU - Navi, Liat Rahamim Ben
AU - Tsukerman, Anna
AU - Feldman, Alona
AU - Melamed, Philippa
AU - Tomic, Melanija
AU - Stojilkovic, Stanko S.
AU - Boehm, Ulrich
AU - Seger, Rony
AU - Naor, Zvi
N1 - Publisher Copyright:
© 2017 Rahamim-Ben Navi, Tsukerman, Feldman, Melamed, Tomic, Stojilkovic, Boehm, Seger and Naor.
PY - 2017/6/21
Y1 - 2017/6/21
N2 - We have previously described a signaling complex (signalosome) associated with the GnRH receptor (GnRHR). We now report that GnRH induces bleb formation in the gonadotrope-derived LβT2 cells. The blebs appear within ~2 min at a turnover rate of ~2-3 blebs/min and last for at least 90 min. Formation of the blebs requires active ERK1/2 and RhoA-ROCK but not active c-Src. Although the following ligands stimulate ERK1/2 in LβT2 cells: EGF > GnRH > PMA > cyclic adenosine monophosphate (cAMP), they produced little or no effect on bleb formation as compared to the robust effect of GnRH (GnRH > PMA > cAMP > EGF), indicating that ERK1/2 is required but not sufficient for bleb formation possibly due to compartmentalization. Members of the above mentioned signalosome are recruited to the blebs, some during bleb formation (GnRHR, c-Src, ERK1/2, focal adhesion kinase, paxillin, and tubulin), and some during bleb retraction (vinculin), while F-actin decorates the blebs during retraction. Fluorescence intensity measurements for the above proteins across the cells showed higher intensity in the blebs vs. intracellular area. Moreover, GnRH induces blebs in primary cultures of rat pituitary cells and isolated mouse gonadotropes in an ERK1/2-dependent manner. The novel signalosome-bleb pathway suggests that as with the signalosome, the blebs are apparently involved in cell migration. Hence, we have extended the potential candidates which are involved in the blebs life cycle in general and for the GnRHR in particular.
AB - We have previously described a signaling complex (signalosome) associated with the GnRH receptor (GnRHR). We now report that GnRH induces bleb formation in the gonadotrope-derived LβT2 cells. The blebs appear within ~2 min at a turnover rate of ~2-3 blebs/min and last for at least 90 min. Formation of the blebs requires active ERK1/2 and RhoA-ROCK but not active c-Src. Although the following ligands stimulate ERK1/2 in LβT2 cells: EGF > GnRH > PMA > cyclic adenosine monophosphate (cAMP), they produced little or no effect on bleb formation as compared to the robust effect of GnRH (GnRH > PMA > cAMP > EGF), indicating that ERK1/2 is required but not sufficient for bleb formation possibly due to compartmentalization. Members of the above mentioned signalosome are recruited to the blebs, some during bleb formation (GnRHR, c-Src, ERK1/2, focal adhesion kinase, paxillin, and tubulin), and some during bleb retraction (vinculin), while F-actin decorates the blebs during retraction. Fluorescence intensity measurements for the above proteins across the cells showed higher intensity in the blebs vs. intracellular area. Moreover, GnRH induces blebs in primary cultures of rat pituitary cells and isolated mouse gonadotropes in an ERK1/2-dependent manner. The novel signalosome-bleb pathway suggests that as with the signalosome, the blebs are apparently involved in cell migration. Hence, we have extended the potential candidates which are involved in the blebs life cycle in general and for the GnRHR in particular.
KW - Blebs
KW - ERK
KW - GnRH
KW - GnRH receptor
KW - Gonadotropes
KW - Signalosome
UR - http://www.scopus.com/inward/record.url?scp=85021217413&partnerID=8YFLogxK
U2 - 10.3389/fendo.2017.00133
DO - 10.3389/fendo.2017.00133
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
AN - SCOPUS:85021217413
SN - 1664-2392
VL - 8
JO - Frontiers in Endocrinology
JF - Frontiers in Endocrinology
IS - JUN
M1 - 133
ER -