Zona pellucida: Difference between revisions

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A specific cell type that proliferates in association with the oocyte within the developing [[F#follicle|follicles]] of the [[O#ovary|ovary]]. These cells form the [[F#follicle|follicle]] stratum granulosa and are also given specific names based upon their position within the [[F#follicle|follicle]]. In the [[A#antral_follicle|antral follicle]], [[M#membrana_granulosa|membrana granulosa]] sits on the [[F#follicular_basal_lamina|follicular basal lamina]] and lines the antrum as a stratified epithelium. The [[C#cumulus_oophorus|cumulus oophorus]] is a column of granulosa cells that attaches the oocyte to the [[F#follicle|follicle]] wall. The [[C#corona_radiata|corona radiata]] are the [[G#granulosa cell|granulosa cells]] that directly surround the oocyte, and are released along with it at ovulation. Following ovulation the corona radiata provide physical protection to the oocyte and granulosa cells within the ovulating [[F#follicle|follicle]] contribute to corpus luteum.
A specific cell type that proliferates in association with the oocyte within the developing [[F#follicle|follicles]] of the [[O#ovary|ovary]]. These cells form the [[F#follicle|follicle]] stratum granulosa and are also given specific names based upon their position within the [[F#follicle|follicle]]. In the [[A#antral_follicle|antral follicle]], [[M#membrana_granulosa|membrana granulosa]] sits on the [[F#follicular_basal_lamina|follicular basal lamina]] and lines the antrum as a stratified epithelium. The [[C#cumulus_oophorus|cumulus oophorus]] is a column of granulosa cells that attaches the oocyte to the [[F#follicle|follicle]] wall. The [[C#corona_radiata|corona radiata]] are the [[G#granulosa cell|granulosa cells]] that directly surround the oocyte, and are released along with it at ovulation. Following ovulation the corona radiata provide physical protection to the oocyte and granulosa cells within the ovulating [[F#follicle|follicle]] contribute to corpus luteum.
====ZP1====
Acronym for '''Z'''ona '''P'''ellucida '''B'''inding '''P'''rotein, a glycoprotein found in zona pellucida surrounding the egg. [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=195000 OMIM - ZP1]
====ZP2====
Acronym for '''Z'''ona '''P'''ellucida '''B'''inding '''P'''rotein 2, a glycoprotein found in zona pellucida surrounding the egg. Before [[F#fertilization|fertilization]] ZP2 binds spermatozoa after the sperm acrosome reaction. After [[F#fertilization|fertilization]] ZP2 is proteolytically cleaved as an initial block to polyspermy. [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=182888 OMIM - ZP2]
====ZP3====
* Acronym for '''Z'''ona '''P'''ellucida '''B'''inding '''P'''rotein 3, a glycoprotein found in zona pellucida surrounding the egg required for initial zona matrix formation and during [[F#fertilization|fertilization]] for species-specific sperm binding. Now thought to exist in 2 isoforms ZP3A and ZP3B (a second polymorphic allele). [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=182889 OMIM - ZP3]
* Zona pellucida glycoprotein ZP3 and fertilization in mammals. Litscher ES, Williams Z, Wassarman PM. Mol Reprod Dev. 2009 Oct;76(10):933-41. Review. [http://www.ncbi.nlm.nih.gov/pubmed/19504560 PMID: 19504560]
====ZPBP1====
Acronym for '''Z'''ona '''P'''ellucida '''B'''inding '''P'''rotein 1 A spermatozoa protein found located on the acrosome surface.


==References==
==References==

Revision as of 17:38, 22 September 2010

Introduction

Early zygote.jpg

(Latin, zona pellucida = transparent zone) A specialized extracellular matrix surrounding the developing oocyte (egg, ovum) within each follicle within the ovary. This thick matrix is thought to be formed by secretions from the oocyte and the follicle granulosa cells and consists of three types of zona pellucida glycoproteins ZP1, ZP2 and ZP3 which have different roles in fertilization.

Following fertilization, the zona pellucida also surrounds the blastocyst during the first week of development, from which it "hatches".

The zona pellucida has a role in fertilization, sperm binding, preventing polyspermy, blastocyst development and preventing premature implantation (ectopic pregnancy).

CSt3.jpg

Links: Carnegie stage 1 | Carnegie stage 3 | Science Lecture - Cell Division and Fertilization

Original page links: Week 1 - Fertilization | Week 1 - Oogenesis |

Some Recent Findings

  • Zona pellucida glycoprotein-1 binds to spermatozoa and induces acrosomal exocytosis[1] "These studies revealed for the first time that in humans ZP1, in addition to ZP3 and ZP4, binds to capacitated spermatozoa and induces acrosomal exocytosis."

Zona Pellucida Glycoproteins

These glycoproteins share several common structural features

  1. N-terminal hydrophobic signal peptide sequence
  2. potential N- and O-linked glycosylation sites
  3. a C-terminal hydrophobic transmembrane-like domain (TMD)
  4. a potential consensus proprotein convertase (furin) cleavage site (CFCS) upstream of TMD,
  5. "ZP domain"

Terms

acrosome reaction

The chemical change within the spermatozoa following binding to the zona pellucida, that leads to the release of acrosomal enzymatic contents. These enzymes degrade the zona pellucida and allow a spermatozoa to penetrate an oocyte.

granulosa cell

A specific cell type that proliferates in association with the oocyte within the developing follicles of the ovary. These cells form the follicle stratum granulosa and are also given specific names based upon their position within the follicle. In the antral follicle, membrana granulosa sits on the follicular basal lamina and lines the antrum as a stratified epithelium. The cumulus oophorus is a column of granulosa cells that attaches the oocyte to the follicle wall. The corona radiata are the granulosa cells that directly surround the oocyte, and are released along with it at ovulation. Following ovulation the corona radiata provide physical protection to the oocyte and granulosa cells within the ovulating follicle contribute to corpus luteum.

References

  1. <pubmed>20504872</pubmed>


Search NCBI Bookshelf zona pellucida | acrosome reaction

Search Pubmed

July 2010 "zona pellucida" All (4801) Review (582) Free Full Text (1408)


Search Pubmed zona pellucida | acrosome reaction

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Cite this page: Hill, M.A. (2024, June 2) Embryology Zona pellucida. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Zona_pellucida

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G