Novel regulated expression of the SLIT/ROBO pathway in the ovary: possible role during luteolysis in women.
The human corpus luteum (CL) undergoes luteolysis, associated with marked tissue and vascular remodeling, unless conception occurs and the gland is rescued by human chorionic gonadotropin (hCG). In Drosophila the Slit gene product, a secreted glycoprotein, acts as a ligand for the roundabout (robo) transmembrane receptor. Together they influence the guidance and migration of neuronal and nonneuronal cells. In vertebrates three Slit (Slit1, Slit2, Slit3) and four Robo (Robo1, Robo2, Robo3/Rig-1, Robo4/Magic Robo) genes have been identified. ROBO1, SLIT2, and SLIT3 are also inactivated in human cancers and may regulate apoptosis and metastasis. Because processes such as apoptosis and tissue remodeling occur during the regression of the CL, the aim of this study was to investigate the expression, regulation, and effects of the SLIT and ROBO genes in human luteal cells. Immunohistochemistry and RT-PCR revealed that SLIT2, SLIT3, ROBO1, and ROBO2 are expressed in luteal steroidogenic cells and fibroblast-like cells of the human CL. Furthermore, using real-time quantitative PCR, expression of SLIT2, SLIT3, and ROBO2 was maximal in the late-luteal phase and significantly reduced after luteal rescue in vivo with exogenous hCG (P<0.05). Additionally, hCG significantly inhibited SLIT2, SLIT3, and ROBO2 expression in cultured luteinized granulosa cells (P<0.05). Blocking SLIT-ROBO activity increased migration and significantly decreased levels of apoptosis in primary cultures of luteal cells (P<0.05). Overall, these results suggest the SLIT/ROBO pathway could play an important role in luteolysis in women.
Medical Research Council Human Reproductive Sciences Unit, Centre for Reproductive Biology, Department of Reproductive and Developmental Sciences, The Queen's Medical Research Institute, Edinburgh, Scotland, United Kingdom. r.dickinson@hrsu.mrc.ac.uk
Rachel E
RE
Dickinson
Michelle
M
Myers
W Colin
WC
Duncan
D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D006063:Chorionic Gonadotropin / Q000494:pharmacology; D003338:Corpus Luteum / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D005260:Female; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D015870:Gene Expression / Q000187:drug effects / Q000502:physiology; D006107:Granulosa Cells / Q000166:cytology / Q000502:physiology; D006801:Humans; D006854:Hydrocortisone / Q000494:pharmacology; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism; D008184:Luteal Cells / Q000166:cytology / Q000502:physiology; D003341:Luteolysis / Q000502:physiology*; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics* / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism; D011971:Receptors, Immunologic / Q000235:genetics* / Q000378:metabolism; D000097905:Roundabout Proteins; D000098552:Slit Homolog 2 Protein
D006063:Chorionic Gonadotropin; D006854:Hydrocortisone; D036341:Intercellular Signaling Peptides and Proteins; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D000097905:Roundabout Proteins; D000098552:Slit Homolog 2 Protein; C498890:ROBO2 protein, human; C499630:ROBO3 protein, human; C462951:ROBO4 protein, human; C492289:SLIT1 protein, human; C498990:SLIT3 protein, human