Expression of nectin-2 in mouse granulosa cells

doi:10.1016/j.ejogrb.2004.12.019

European Journal of Obstetrics & Gynecology and Reproductive Biology

Volume 121, Issue 1, 1 July 2005, Pages 71-76

https://doi.org/10.1016/j.ejogrb.2004.12.019 Get rights and content

Abstract

Objective:

The development and maturation of the ovarian follicles are characterized by structural changes that require components involved in cell–cell adhesion systems. Recently a novel group of cell adhesion molecules named nectins has been identified. The present study examined expression and cell-specific localization of nectins during mouse follicular development.

Study design:

Expression of nectins in mouse ovary was investigated by immnuoblot analysis and immunohistochemistry. More precise localization was determined by electron microscopy.

Results:

Immunoblot analysis revealed expression of nectin-2 and nectin-3 but not nectin-1 in ovarian granulosa cells. Immunohistochemistry demonstrated expression of nectin-2 at cell–cell adhesion sites of granulosa cell layer in the primary and preantral follicles. Especially, intense immunoreactivity of nectin-2 accumulated around the zona pellucida. In antral follicles, the intensity of nectin-2 expression on granulosa cells was decreased. By electron microscopy nectin-2 was detected not only on thin extensions of granulosa cells penetrating the zona pellucida, but also on the attachment sites between thin extensions of granulosa cells and oocyte surface.

Conclusion:

The restricted expression of nectin-2 in the granulosa cells of primary and preantral follicles might reflect some of the molecular changes in cell–cell adhesion during early follicular development.

Introduction

The mammalian ovary undergoes dynamic morphological changes during the reproductive cycle. During ovarian follicle development and maturation, the follicle undergoes significant cellular rearrangements [1], [2]. Considerable progress has been made in our understanding of the regulation of the physiological and molecular events involved in the development and maturation of ovarian follicles [3], [4]. However, the underlying mechanisms involved in the morphological processes during ovarian folliculogenesis have not been fully elucidated.

The cellular rearrangements during the ovarian follicle maturation are dependent on the maintenance of appropriate cell–cell contact [5]. Cell–cell adhesion plays essential roles in various functions, including the control of cell growth and tissue morphogenesis [6], [7]. In polarized epithelial cells, cell–cell adhesion sites form a specialized membrane structure, composed of tight junctions, adherence junctions and desmosomes [6]. The adherence junctions and desmosomes that appear at early stages of follicular development are intrinsically coupled to the thin filament and intermediate filament network, respectively [5], [8]. The functional units of cell–cell adhesion are typically composed of cell adhesion molecules (CAMs) and cytoplasmic peripheral membrane proteins [7], which are linked to the cytoskeleton. CAMs mediate cell–cell adhesion at the extracellular surface by homophilic or heterophilic interactions and determine the specificity of cell–cell recognition. CAMs are classified into groups that include the cadherin family [9], [10], the Ig superfamily (IgCAM) [11], the integrin family [12], and the selectin family [12].

Recently, novel cell–cell adhesion molecules named nectins [13], [14] have been identified. Nectins are Ca²⁺-independent immunoglobulin-like CAMs that mediate cell–cell adhesion by homophilic and heterophilic interactions. Nectins are localized at the epithelial cadherin (E-cadherin)-based cell–cell adherence junctions and comprise a family consisting of four members, nectin-1, -2, -3, and -4 [13], [14]. Bouchard et al. [15] and Mueller et al. [16] have reported that nectin-2-deficient mice exhibit male-specific infertility and have defects in the later steps of sperm morphogenesis, which indicates a role for this protein in the organization and reorganization of the cytoskeleton during spermiogenesis. The fact that the nectin family is colocalized with the cadherin family at cell–cell adherence junctions in epithelial cells [13], [14], [17] suggests the intriguing possibility that the nectin family is also involved in morphogenetic processes controlling ovarian folliculogenesis. However, to date, the expression or cell-specific localization of the nectins during ovarian follicular development has not been clarified. In this study, we examined the behavior of the nectin family during follicle formation and maturation.

Section snippets

Antibodies

A rabbit polyclonal anti-nectin-1α antibody (Ab) was raised against GST-nectin-1α-CPN (corresponding to aa 379–438) as described [14] and used for immunoblotting. A rat monoclonal anti-nectin-2 Ab which recognizes the extracellular domains of nectin-2 was also produced as previously described [14]. A rat monoclonal anti-nectin-3 Ab was raised as described [18] and used for immunohistochemistry. As a rat monoclonal anti-nectin-3 Ab was not applicable to immunoblotting [18], a rabbit polyclonal

Expression of nectins in mouse ovarian tissue

The expression of nectins in mouse ovarian tissue was first examined by immunoblotting. Total extracts from mouse testis, known to express nectin-2 and nectin-3, were used as a positive control. As shown in Fig. 1(B), nectin-2 was clearly expressed in the testis as two protein bands at about 75 and 80 kDa. The upper band corresponds to nectin-2δ, which is one of the splicing variants of nectin-2, while the lower one is nectin-2α, which is another splicing variant form [14]. In the granulosa

Comment

The adherence junctions have been shown to play an important role during the early stages of follicular development [5], and CAMs participate in the formation of the adherence junctions [21]. Previous studies have shown that cadherins, one member of Ca²⁺-dependent CAMs, are involved in the follicular function [22], [23], [24]. Nectins are one member of a family of Ca²⁺-independent CAMs that mediate cell–cell adhesion in a variety of species [25]. Since the nectin family has roles in

References (31)

J.S. Richards et al.
Molecular mechanisms of ovulation and luteinization
Mol Cell Endocrinol
(1998)
B.M. Gumbiner
Cell adhesion: the molecular basis of tissue architecture and morphogenesis
Cell
(1996)
C.A. Buck
Immunoglobulin superfamily: structure, function and relationship to other receptor molecules
Semin Cell Biol
(1992)
K. Satoh-Horikawa et al.
Nectin-3, a new member of immunoglobulin-like cell adhesion molecules that shows homophilic and heterophilic cell–cell adhesion activities
J Biol Chem
(2000)
I.M. Joyce et al.
Oocyte regulation of kit ligand expression in mouse ovarian follicles
Dev Biol
(1999)
A. Mizoguchi et al.
Localization of Rabphilin-3A on the synaptic vesicle
Biochem Biophys Res Commun
(1994)
S. Tsukita et al.
Molecular linkagae between cadherins and actin filaments in cell–cell adherence junctions
Curr Opin Cell Biol
(1992)
R. Farookhi et al.
Luteinizing hormone receptor induction in dispersed granulosa cells requires estrogen
Mol Cell Endocrinol
(1986)
O.W. Blaschuk et al.
Estradiol stimulates cadherin expression in rat granulosa cells
Dev Biol
(1989)
K. Ozaki-Kuroda et al.
Nectin couples cell–cell adhesion and the actin scaffold at heterotypic testicular junctions
Curr Biol
(2002)

F.L. Barnes et al.

Oocyte maturation

Semin Reprod Med

(2000)

A. Amleh et al.

Mouse genetics provides insight into folliculogenesis, fertilization and early embryonic development

Hum Reprod Update

(2002)

J.S. Richards

Hormonal control of gene expression in the ovary

Endocrinol Rev

(1994)

A. Amsterdam et al.

Structure–function relationships during differentiation of normal and oncogene-transformed granulosa cells

Biol Reprod

(1992)

G.M. Edelman

Cell adhesion molecules in the regulation of animal form and tissue pattern

Annu Rev Cell Biol

(1996)

Cited by (11)

Short communication: Photoperiod impacts ovarian extracellular matrix and metabolic gene expression in Siberian hamsters
2022, Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology
Ovarian cyclicity is variable in adult Siberian hamsters (Phodopus sungorus), who respond to long breeding season photoperiods with follicle development and ovulation, while short photoperiods typical of the non-breeding season induce gonadal atrophy. Recent RNAseq results identified ovarian matrix components and regulators of metabolism as differentially regulated by photoperiod; however, the impact of photoperiod across a full cycle of ovarian regression and recrudescence had not been explored for additional regulators of ovarian metabolism and extracellular matrix components. We hypothesized that matrix and metabolism-related genes would be expressed differentially across photoperiods that mimic breeding and non-breeding season daylengths. Hamsters were housed in one of four photoperiod groups: long day (16 h of light per day: 8 h of dark; LD, controls), short day regressed (8 L:16D; SD, regressed), and females exposed to SD then transferred to LD to stimulate return of ovarian function for 2 (early recrudescence), or 8 (late recrudescence) weeks. Plasma leptin concentrations along with expression of ovarian versican and liver-receptor homolog-1/Nr582 mRNA decreased in SD compared to LD and late recrudescence, while vimentin mRNA expression peaked in early and late recrudescence. Ovarian expression of fibronectin and extracellular matrix protein-1 was low in LD ovaries and increased in regressed and recrudescing groups. Expression of hyaluronidase-2, nectin-2, liver-X receptors-α and-β, and adiponectin mRNA peaked in late recrudescence, with no changes noted for adiponectin receptor-1 and -2. The results offer a first look at the parallels between expression of these genes and the dynamic remodeling that occurs during ovarian regression and recrudescence.
Comparison of Human Antral Follicles of Xenograft versus Ovarian Origin Reveals Disparate Molecular Signatures
2020, Cell Reports
Citation Excerpt :
Within the GC compartment, oophorus and mural fractions could be distinguished by the surface marker PVRL1. Expression of this family of genes in human ovary has not been described previously; mouse GCs specifically express PVRL2 and PVRL3 but not PVRL1 (Kawagishi et al., 2005), underscoring the subtle differences between mouse and human reproductive processes. Functionally, PVRL proteins serve as Ca2+-independent cell adhesion molecules and mediate homophilic and heterophilic cellular interactions (Takahashi et al., 1999; Takai and Nakanishi, 2003) that organize groups of epithelial cells (Mandai et al., 1997); hence, the enrichment of this protein in a subset of GCs may provide a means of compartmentalizing the follicle.
The activation, growth, and maturation of oocytes to an ovulatory phase, termed folliculogenesis, is governed by the orchestrated activity of multiple specialized cell types within the ovary; yet, the mechanisms governing diversification and behavior of discrete cellular sub-populations within follicles are poorly understood. We use bulk and single-cell RNA sequencing to distinguish the transcriptional signature of prospectively isolated granulosa and theca/stroma cell subsets within human antral follicles derived from xenografts or ovaries. The analysis deconstructs phenotypic diversification within small (<4 mm) antral follicles, identifying secreted factors that are differentially enriched between mural and oophorus granulosa cells, and segregating stromal/support and steroidal activity between theca externa and interna, respectively. Multiple factors are differentially expressed in follicles of xenograft versus ovarian origin. These data capture a high-resolution transcriptional signature of granulosa and theca subpopulations and provide a systems-level portrait of cellular diversification in early antral human follicles.
Intercellular communications in ovarian follicles
2016, Reproducao e Climaterio
Durante a foliculogênese em mamíferos, ocorre um longo e complexo processo no qual o oócito adquire a competência necessária para a fecundação. Nesse processo ocorre uma comunicação metabólica bidirecional entre os oócitos e as células somáticas dentro do folículo que garante substratos para o oócito em desenvolvimento. Essa comunicação é mediada pelas junções celulares (junções comunicantes e junções aderentes) presentes nas projeções transzonais. As junções celulares e moléculas de adesão são responsáveis principalmente por promover a adesão entre as células foliculares; mas podem atuar em vias de sinalização celular e na regulação da transcrição gênica nas células somáticas e oócitos. Além disso, as junções comunicantes (junções gap) são canais intermembranares que intermediam a comunicação entre essas células através da passagem de pequenas moléculas. Essas junções comunicantes são compostas por proteínas denominadas conexinas; as conexinas 37 e 43 são as predominantes nos folículos ovarianos. Dessa forma, o conhecimento acerca das junções celulares é de extrema importância para o estudo da foliculogênese. A presente revisão teve como objetivo abordar os principais tipos de junções celulares existentes entre as células foliculares, com destaque para as junções gap e as principais proteínas de membranas (conexinas) presentes nos diferentes estágios do desenvolvimento folicular.
During the mammalian folliculogenesis, a long and complex process occurs, which the oocyte acquires the necessary competence for fecundation. In this process there is a metabolic bidirectional communication among the oocyte and somatic cells inside the follicle, which provides substrates for the oocyte developmental competence. This communication is mediated by cellular junctions (occlusions, adherens and gap junctions) localized in the transzonal projections. Cellular junctions and adhesion mollecules are responsable mainly for promoving the adhesion among follicular cells, however they can act in cellular signaling pathways and in regulation of genic transcription in the follicular cells and oocyte. Moreover, the communication junctions (gap junctions) are intermembrane channels that intermediate the communication among these cells through the passage of small molecules. These gap junctions are composed by connexins, of which the connexins 37 and 43 are the most frequently found in the ovarian follicle. Thus, knowledge of these cellular junctions are of great importance for studying the folliculogenesis process. The aim of this review was to report the main types of cellular junctions localized among the follicular cells, especially the gap junctions and the main membrane proteins (connexins) found in different stages of the follicular development.
Visfatin Affects the Transcriptome of Porcine Luteal Cells during Early Pregnancy
2024, International Journal of Molecular Sciences
Evolution and conservation of Characidium sex chromosomes
2017, Heredity
Regulation of endothelial permeability in the primate corpora lutea: Implications for ovarian hyperstimulation syndrome
2015, Reproduction

View all citing articles on Scopus

View full text