NCBI Summary:
Ephrin receptors and their ligands, the ephrins, mediate numerous developmental processes, particularly in the nervous system. Based on their structures and sequence relationships, ephrins are divided into the ephrin-A (EFNA) class, which are anchored to the membrane by a glycosylphosphatidylinositol linkage, and the ephrin-B (EFNB) class, which are transmembrane proteins. The Eph family of receptors are divided into 2 groups based on the similarity of their extracellular domain sequences and their affinities for binding ephrin-A and ephrin-B ligands. Ephrin receptors make up the largest subgroup of the receptor tyrosine kinase (RTK) family. The protein encoded by this gene is a receptor for ephrin-B family members. [provided by RefSeq, Jul 2008]
General function
Receptor
Comment
Cellular localization
Plasma membrane
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Ovarian function
Ovulation
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Expression regulated by
LH
Comment
Activated receptor tyrosine kinases in granulosa cells of ovulating follicles in mice. Schuermann Y et al. (2018) Successful ovulation requires the actions of gonadotropins along with those mediated by growth factors binding to their receptor tyrosine kinases (RTKs). There are several growth factors such as epidermal growth factor family ligands and interleukins that play a role during ovulation initiated by the preovulatory surge of luteinizing hormone (LH). The aim of this project was to analyze growth factor signaling pathways induced by LH in mouse granulosa cells. Immature female mice were treated with equine chorionic gonadotropin (eCG) followed 48h later by human chorionic gonadotropin (hCG) to induce follicular growth and ovulation. We performed protein array analysis where we identified higher phosphorylation of insulin-like growth factor 1 receptor (IGF1R), the fibroblast growth factor receptor 2 (FGFR2) and ephrin receptor B1 (EPHB1) in granulosa cells at 4h post-hCG compared to 0h hCG (P < 0.05). We report both a significant increase in transcript abundance (P < 0.05) and the phosphorylation level (P < 0.05) of the IGF1R in granulosa cells at hCG4h. The mRNA abundance of the Fgfr2 and Ephb1 receptors remained unaltered upon hCG treatment. Nonetheless, transcript abundance of the fibroblast growth factor 2 (Fgf2) ligand was elevated at hCG4h (P < 0.01). Based on these results we conclude that the preovulatory LH surge activates signaling pathways of IGF1R through increase in the expression of the Igf1r gene in granulosa cells of ovulating follicles in mice. The LH surge also appears to activate FGFR2 IIIc and EPHB1 signaling, although further investigation is required. This article is protected by copyright. All rights reserved.//////////////////
Ovarian localization
Comment
This gene was found through a series of ovarian DNA microarray analyses.