Cellular scaffolds in mammalian eggs.
Cellular scaffolds serve as structural components to which various elements of signal transduction pathways can be associated. The association of components on a scaffold can have several important functions, for example they can: 1) associate upstream regulatory components in a cascade that can increase the speed of response to a stimulus; 2) restrict access of substrates to enzymes associated with the scaffold; 3) permit cross talk between distinct signaling pathways, and; 4) aid in the establishment of cellular polarity. The conversion of the mammalian egg into the zygote requires many rapid alterations during a distinct time frame to mediate the biochemical and structural changes that occur. Cellular scaffolds provide a mechanism that can perform these rapid, highly orchestrated changes. They can permit interaction between distinct calcium-dependent pathways and also can provide a means for the calcium signal, that is initiated by fertilization, to act on calcium-independent pathways. This review considers various lines of evidence suggesting that in the mammalian egg, the meiotic spindle serves as a cellular scaffold that permits coordination among several signaling pathways essential for fertilization and the initiation of early development.
Baluch
D Page
DP
Department of Biology, Molecular and Cellular Biology Program, Arizona State University, Tempe, Arizona 85287-1501, USA.
Capco
David G
DG
D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism; D016764:Cell Polarity / Q000502:physiology; D005306:Fertilization / Q000502:physiology; D006801:Humans; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism; D010063:Ovum / Q000737:chemistry* / Q000166:cytology / Q000201:enzymology / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D015053:Zygote / Q000737:chemistry / Q000201:enzymology
D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D020928:Mitogen-Activated Protein Kinases