NCBI Summary:
Laminin, alpha 1; possible extracellular matrix protein; member of a family basement membrane ECM proteins
General function
Cell adhesion molecule
Comment
Cellular localization
Extracellular Matrix
Comment
Ovarian function
Follicle development
Comment
Expression regulated by
LH
Comment
Ovarian localization
Granulosa
Comment
Changes in mouse granulosa cell gene expression during early luteinization. McRae RS et al. Changes in gene expression during granulosa cell luteinization have been measured using serial analysis of gene expression (SAGE). Immature normal mice were treated with pregnant mare serum gonadotropin (PMSG) or PMSG followed, 48 h later, by human chorionic gonadotropin (hCG). Granulosa cells were collected from preovulatory follicles after PMSG injection or PMSG/hCG injection and SAGE libraries generated from the isolated mRNA. The combined libraries contained 105,224 tags representing 40,248 unique transcripts. Overall, 715 transcripts showed a significant difference in abundance between the two libraries of which 216 were significantly down-regulated by hCG and 499 were significantly up-regulated. Among transcripts differentially regulated, there were clear and expected changes in genes involved in steroidogenesis as well as clusters of genes involved in modeling of the extracellular matrix, regulation of the cytoskeleton and intra and intercellular signaling. The SAGE libraries described here provide a base for functional investigation of the regulation of granulosa cell luteinization.
Follicle stages
Primary, Secondary, Antral, Preovulatory
Comment
Extracellular matrix of the developing ovarian follicle.
Rodgers RJ, et al 2003 ..
Ovaries can be considered tissues in which endocrine organs - follicles and corpora lutea - continually grow and regress. Follicles have both epithelial and stromal layers in which cell migration or movement, cell division, specialization and differentiation, and death occur. A fluid-filled antrum develops and at ovulation the epithelial cells undergo an epithelial to mesenchymal transition into luteal cells. Although growth factors and hormones are very important in some of these processes, the extracellular matrix participates in all of them. Importantly, the matrix is diverse in composition and cells rarely behave without reference to the composition and structure of the matrix. When follicles commence growing, the follicular basal lamina changes in its composition from containing all six alpha chains of collagen type IV to only alpha1 and alpha2. Perlecan and nidogen 1 subsequently become components of the follicular basal lamina, and there is an increase in the amount of laminin chains alpha1, beta2 and gamma1, at least in cows. Late in follicular developent and on atresia some follicles contain laminin alpha2. On atresia the follicular basal lamina is not degraded as occurs at ovulation, but can be breached by cells from the thecal layer if granulosa cells no longer align it.