|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Department of Animal Science, Cornell University, Ithaca, New York 14853
Betaglycan was originally characterized as the type III receptor for TGFß, yet recent research has indicated that betaglycan can serve as an accessory receptor for inhibin. To understand better the action of inhibin in avian follicular development, we have investigated the expression of betaglycan in the pituitary gland and ovary of the hen. In experiments 1 and 2, betaglycan mRNA was detected at 6 kilobases (kb) by Northern blot analysis (n = 5) in chicken pituitary, granulosa, and theca layers and whole ovary. Expression of betaglycan was greatest in the pituitary gland in experiment 1 and greater in the granulosa layer of small yellow follicles (SYF) compared with the granulosa layer of larger follicles. In experiment 2, betaglycan mRNA was more abundantly expressed in the theca layer compared with the granulosa layer for all follicle sizes, although there was no significant difference in betaglycan expression in the theca layer among follicle sizes. In experiment 3, immunohistochemical analysis revealed betaglycan protein in the anterior pituitary as well as in the ovary (n = 4) and SYF (n = 4). Colocalization studies revealed a high abundance of cells within the anterior pituitary expressing both betaglycan and FSH (n = 4). Betaglycan protein was found in the granulosa layer; however, markedly enhanced staining was observed in the theca layer of ovarian follicles. Our results provide evidence for expression of betaglycan mRNA and protein colocalization with FSH in the anterior pituitary, consistent with known inhibin effects. Ovarian localization of betaglycan, particularly in the theca layer, suggests a paracrine role for inhibin in the hen.
2 Correspondence: Patricia A Johnson, Department of Animal Science, Cornell University, 202 Morrison Hall, Ithaca, NY 14853. FAX: 607 255 9829; paj1{at}cornell.edu
This article has been cited by other articles:
![]() |
T. M Lovell, S. L Al-Musawi, R. T Gladwell, and P. G Knight Gonadotrophins modulate hormone secretion and steady-state mRNA levels for activin receptors (type I, IIA, IIB) and inhibin co-receptor (betaglycan) in granulosa and theca cells from chicken prehierarchical and preovulatory follicles Reproduction, June 1, 2007; 133(6): 1159 - 1168. [Abstract] [Full Text] [PDF] |
||||
![]() |
T M Lovell, P G Knight, and R T Gladwell Differential expression of mRNAs encoding the putative inhibin co-receptor (betaglycan) and activin type-I and type-II receptors in preovulatory and prehierarchical follicles of the laying hen ovary J. Endocrinol., February 1, 2006; 188(2): 241 - 249. [Abstract] [Full Text] [PDF] |
||||
![]() |
T M Lovell, P G Knight, and R T Gladwell Variation in pituitary expression of mRNAs encoding the putative inhibin co-receptor (betaglycan) and type-I and type-II activin receptors during the chicken ovulatory cycle J. Endocrinol., September 1, 2005; 186(3): 447 - 455. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |