Fertilization

Fertilization (mosly mice and mammals)

Chapter 10

Cumulus Cells

Follicle cells shed with the egg

when it is released

Hyaluronic Acid

major component of the extracellular matrix

Hyaluronidase

enzymein the sperm head

Zona Pellucida

Extracellular glycoproteinssurrounding the oocyte,secreted by follicle cells

ZP1, ZP2, ZP3

Three glycoproteinsthat comprise the zona

Glycoprotein

Protein with sugars attached

GalT

The sperm-surface proteinthat binds to ZP3,

resulting in the arcosome reaction

Arcosome Reaction

Rapid exocytosis of the arcosomal vesicle

containing arcosin

Arcosin

A serine proteasethat digests a path

through the zona

ADAM Proteins

Sperm proteins that bindintegrins on the egg surface

Integrins

“...receptors that mediate attachment...”

Cell fusion

The joining of membranesand ultimately of cells

leads to the rise ofintracellular [Ca2+] and

Release of cortical granules

Secretory vesicles containing glycosidases and proteases

modifies the zona so sperm can no longer bind

Glycosidase

Enzyme that hydrolyzes glycosidic linkages

Preventspolyspermy

Fertilization of an eggby more than one sperm

Completion ofsecond meiotic division(expulsion of second polar body)

Pronuclei breakdown.

Chromosomes align for first cleavage.

Centriole forms the firstmitotic spindle