| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
ARTICLES |
a The Laboratories for Reproductive Biology,
b Departments of Pediatrics and
c Cell Biology & Anatomy, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599
d Laboratory of Reproductive and Developmental Toxicology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina 27709
The insulin-like growth factor-II/cation-independent mannose 6-phosphate (IGF-II/M6P) receptor transduces signals after binding IGF-II or M6P-bearing growth factors. We hypothesized that this receptor relays paracrine signals between Sertoli cells and spermatogonia in the basal compartment of the seminiferous epithelium. For these studies spermatogonia were isolated from 8-day-old mice with purity >95% and viability >85% after overnight culture. The IGF-II/M6P receptors were present on the surface of spermatogonia, as detected by indirect immunofluorescence. We determined that both IGF-II and M6P-glycoproteins in Sertoli cell conditioned medium (SCM) modulate gene expression in isolated spermatogonia. The IGF-II produced dose-dependent increases in both rRNA and c-fos mRNA. These effects were mediated specifically by IGF-II/M6P receptors, as shown by studies using IGF-II analogues that are specific agonists for either IGF-I or IGF-II receptors. The SCM treatment also induced dose-dependent increases in rRNA levels, and M6P competition showed that this response required interaction with IGF-II/M6P receptors. The M6P-glycoproteins isolated from SCM by IGF-II/M6P receptor affinity chromatography increased spermatogonial rRNA levels at much lower concentrations than required by SCM treatment, providing further evidence for the paracrine activity of Sertoli M6P-glycoproteins. These results demonstrate that Sertoli cells secrete paracrine factors that modulate spermatogonial gene expression after interacting with cell-surface IGF-II/M6P receptors.
1 This research was supported by NICHD/NIH through HD26485 (D.A.O.) and cooperative agreement U54 HD35041 as part of the Specialized Cooperative Centers Program in Reproductive Research. Funding was also provided by NIH CA16086 (UNC Lineberger Comprehensive Cancer Center), and additional salary support for J.K.T. was provided by the Andrew W. Mellon Foundation.
2 Correspondence: James K. Tsuruta, Laboratories for Reproductive Biology, Pediatrics Dept. CB#7500, 377 Medical Sciences Research Building, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7500. FAX: 919 966 2204; jtsuruta{at}excite.com
This article has been cited by other articles:
|
|
 |
|
  S. Sipione, K. C. Simmen, S. J. Lord, B. Motyka, C. Ewen, I. Shostak, G. R. Rayat, J. M. Dufour, G. S. Korbutt, R. V. Rajotte, et al. Identification of a Novel Human Granzyme B Inhibitor Secreted by Cultured Sertoli Cells J. Immunol., October 15, 2006; 177(8): 5051 - 5058. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. H. Ing, A. M. Laughlin, D. D. Varner, T. H. Welsh Jr., D. W. Forrest, T. L. Blanchard, and L. Johnson Gene Expression in the Spermatogenically Inactive "Dark" and Maturing "Light" Testicular Tissues of the Prepubertal Colt J Androl, July 1, 2004; 25(4): 535 - 544. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Chandrashekar, D. Zaczek, and A. Bartke The Consequences of Altered Somatotropic System on Reproduction Biol Reprod, July 1, 2004; 71(1): 17 - 27. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. J. Saris, M. M.E.D. van den Eijnden, J. M.J. Lamers, P. R. Saxena, M. A.D.H. Schalekamp, and A.H. J. Danser Prorenin-Induced Myocyte Proliferation: No Role for Intracellular Angiotensin II Hypertension, February 1, 2002; 39(2): 573 - 577. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. M. Eddy Male Germ Cell Gene Expression Recent Prog. Horm. Res., January 1, 2002; 57(1): 103 - 128. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
