title: Model of the delayed translation of cyclin B maternal mRNA after sea urchin fertilization.
abstract: Sea urchin eggs exhibit a cap-dependent increase in protein synthesis within minutes after fertilization. This rise in protein synthesis occurs at a constant rate for a great number of proteins translated from the different available mRNAs. Surprisingly, we found that cyclin B, a major cell-cycle regulator, follows a synthesis pattern that is distinct from the global protein population, so we developed a mathematical model to analyze this dissimilarity in biosynthesis kinetic patterns. The model includes two pathways for cyclin B mRNA entry into the translational machinery: one from immediately available mRNA (mRNAcyclinB) and one from mRNA activated solely after fertilization (XXmRNAcyclinB). Two coefficients, α and β, were added to fit the measured scales of global protein and cyclin B synthesis, respectively. The model was simplified to identify the synthesis parameters and to allow its simulation. The calculated parameters for activation of the specific cyclin B synthesis pathway after fertilization included a kinetic constant (ka) of 0.024 sec-1, for the activation of XXmRNAcyclinB, and a critical time interval (t2) of 42 min. The proportion of XXmRNAcyclinB form was also calculated to be largely dominant over the mRNAcyclinB form. Regulation of cyclin B biosynthesis is an example of a select protein whose translation is controlled by pathways that are distinct from housekeeping proteins, even though both involve the same cap-dependent initiation pathway. Therefore, this model should help provide insight to the signaling utilized for the biosynthesis of cyclin B and other select proteins. Mol. Reprod. Dev. 83: 1070-1082, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: CNRS UMR 6241, Laboratoire LINA, Université de Nantes, Nantes, France.|CNRS, IRISA-UMR 6074, Campus de Beaulieu, Rennes, France.|INRIA, Centre Rennes-Bretagne Atlantique, Symbiose, Campus de Beaulieu, Rennes, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Picard
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.|CNRS, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.
authors.forename: Odile
authors.initials: O
authors.lastname: Mulner-Lorillon
authors.affiliation: CNRS UMR 6241, Laboratoire LINA, Université de Nantes, Nantes, France.
authors.forename: Jérémie
authors.initials: J
authors.lastname: Bourdon
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.|CNRS, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.
authors.forename: Julia
authors.initials: J
authors.lastname: Morales
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.|CNRS, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.
authors.forename: Patrick
authors.initials: P
authors.lastname: Cormier
authors.affiliation: CNRS, IRISA-UMR 6074, Campus de Beaulieu, Rennes, France.|INRIA, Centre Rennes-Bretagne Atlantique, Symbiose, Campus de Beaulieu, Rennes, France.
authors.forename: Anne
authors.initials: A
authors.lastname: Siegel
authors.affiliation: Sorbonne Universités, UPMC Univ Paris 06, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.|CNRS, UMR 8227, Integrative Biology of Marine Models, Translation Cell Cycle and Development, Station Biologique de Roscoff, Roscoff Cedex, France.
authors.forename: Robert
authors.initials: R
authors.lastname: Bellé
mesh_terms: D000818:Animals; D019926:Cyclin B / Q000096:biosynthesis*; D005260:Female; D005306:Fertilization; D008954:Models, Biological; D010063:Ovum / Q000166:cytology / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000502:physiology*; D023121:RNA, Messenger, Stored / Q000378:metabolism*; D012617:Sea Urchins / Q000378:metabolism
chemical_list: D019926:Cyclin B; D023121:RNA, Messenger, Stored