Zona pellucida

Zona pellucida

Infobox Anatomy
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Caption2 = Human ovum. The zona pellucida is seen as a thick clear girdle surrounded by the cells of the corona radiata.
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MeshName = Zona+Pellucida
MeshNumber = A05.360.490.690.950
DorlandsPre = z_01
DorlandsSuf = 12869767
The zona pellucida (or zona striata in older texts) is a glycoprotein membrane surrounding the plasma membrane of an oocyte. It is a vital constitutive part of the latter, external but not extraneous to it.

This structure binds spermatozoa, and is required to initiate the acrosome reaction.

The zona glycoprotein, ZP3, is responsible for sperm binding, adhering to proteins on the sperm plasma membrane. There is evidence that ZP3 is then involved in the induction of the acrosome reaction, whereby a spermatozoon releases the contents of the acrosomal vesicle.

Function in humans

In humans, five days after the fertilization, the blastocyst performs zona hatching; the zona pellucida degenerates and decomposes to be replaced by the underlying layer of trophoblastic cells.

The zona pellucida is essential for oocyte death and fertilization.

Immunocontraception

Glycoproteins in ZP1, 2, and 3 are targets for immunocontraception.

In non-mammalian animals, the zona pellucida (called vitelline layer) plays an important role in preventing breeding of different species, especially in species that fertilize outside of the body (e.g. fish).

The zona pellucida is commonly used to control wildlife population problems by immunocontraception. When the zona pellucida of one animal species is injected into the bloodstream of another, it results in sterility of the second species due to immune response. This effect can be temporary or permanent, depending on the method used. In New Jersey, Porcine zona pellucida is used to keep deer populations low, and this process is commonly referred to as "spay-vac".

Three Major Glycoproteins

*ZP3 allows species-specific sperm binding
*ZP2 mediates subsequent sperm binding
*ZP1 cross-links ZP2 and ZP3. It is important for structural integrity of zona pellucida but not essential for fertilization.


=Additional

References

*

*Bagnell, C. 2005. "Animal Reproduction". Rutgers University Department of Animal Sciences.

External links

* - "Female Reproductive System: ovary, cumulus oophorus "
* - "Female Reproductive System: ovary, multilaminar primary follicle"
* - "Mammal, canine ovary (LM, High)"
* [http://staff.um.edu.mt/acus1/FERTILIZATION_files/image002.jpgImage at um.edu.mt]
* [http://staff.um.edu.mt/acus1/GAMETOGENESIS_files/image019.gifImage at um.edu.mt]


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Look at other dictionaries:

  • Zona pellucida — Zona o na, n.; pl. {Zon[ae]}. [L., a girdle. See {Zone}.] A zone or band; a layer. [1913 Webster] {Zona pellucida}. [NL.] (Biol.) (a) The outer transparent layer, or envelope, of the ovum. It is a more or less elastic membrane with radiating… …   The Collaborative International Dictionary of English

  • zona pellucida — zona pellucida. См. вителлиновый слой. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Zona pellucĭda — Zona pellucĭda, s. Embryonalhüllen …   Meyers Großes Konversations-Lexikon

  • Zona pellucida — Zona pellucida, extrazelluläre, glykoproteinreiche Schicht, die als Eihülle das Säugerei umgibt …   Deutsch wörterbuch der biologie

  • zona pellucida — [zō′nə pə lo͞o′si də] n. pl. zonae pellucidae [zō′nē pə lo͞o′si dē] the clear, thick outer membrane that surrounds and protects the mature egg of a mammal: it has receptors on its surface that bind with sperm cells …   English World dictionary

  • Zona pellucida — Эмбрион человека, окруженный Zona pellucida. лат. Zona pellucida (ранее также zona stria …   Википедия

  • Zona pellucida — Menschliche Eizelle mit der sie als weißer Gürtel umgebenden Zona pellucida, welche ihrerseits in die Corona radiata eingebettet ist. Die Zona pellucida oder Glashaut ist eine Schutzhülle um die Eizelle (Ovozyte), die von den kubischen… …   Deutsch Wikipedia

  • Zona pellucida — The strong membrane that forms around an ovum as it develops in the ovary. The membrane remains in place during the egg’s travels through the fallopian tube. To fertilize the egg, a sperm must penetrate the thinning zona pellucida. If… …   Medical dictionary

  • Zona pellucida — skaidrioji sritis statusas T sritis embriologija atitikmenys: lot. Membrana pellucida; Zona pellucida ryšiai: platesnis terminas – danga sinonimas – skaidrioji membrana …   Medicininės histologijos ir embriologijos vardynas

  • Zona pellucida — skaidrioji sritis statusas T sritis histologija, ląstelių chemija, histologinė chemija, audinių kultūra atitikmenys: lot. Zona pellucida ryšiai: platesnis terminas – spindulinis vainikas siauresnis terminas – ovocitas sinonimas – skaidrioji zona …   Veterinarinės anatomijos, histologijos ir embriologijos terminai

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