PUBLICATION
Calcium transients accompany ooplasmic segregation in zebrafish embryos
- Authors
- Leung, C.F., S.E. Webb, and A.L. Miller
- ID
- ZDB-PUB-971111-3
- Date
- 1998
- Source
- Development, growth & differentiation 40: 313-326 (Journal)
- Registered Authors
- Leung, Christina F., Miller, Andrew L., Webb, Sarah E.
- Keywords
- aequorin; calcium; ooplasmic segregation; zebrafish
- MeSH Terms
-
- Aequorin/metabolism
- Aequorin/pharmacology
- Animals
- Buffers
- Calcium/metabolism*
- Calcium/pharmacology
- Cell Division/drug effects
- Cell Division/physiology
- Cell Polarity/drug effects
- Cytochalasin B/pharmacology
- Cytoplasmic Streaming/drug effects
- Embryo, Nonmammalian/cytology
- Embryo, Nonmammalian/drug effects
- Embryo, Nonmammalian/physiology
- Female
- Luminescent Measurements
- Male
- Microinjections
- Ovum/chemistry
- Ovum/drug effects
- Ovum/physiology
- Time Factors
- Zebrafish/embryology*
- PubMed
- 9639359 Full text @ Dev. Growth Diff.
Citation
Leung, C.F., S.E. Webb, and A.L. Miller (1998) Calcium transients accompany ooplasmic segregation in zebrafish embryos. Development, growth & differentiation. 40:313-326.
Abstract
Through the injection of f-aequorin (a calcium-specific luminescent reporter), and the use of an imaging photon detector, transient localized elevations of free cytosolic calcium in the forming blastodisc (BD) and animal hemisphere cortex were visualized that correlated with ooplasmic segregation. The introduction of an appropriate concentration of the weak (KD = 1.5 micromol/L) calcium buffer 5,5'-dibromo-BAPTA results in the dissipation of these calcium domains, and inhibits cytoplasmic streaming and the subsequent formation of a BD at the animal pole. These inhibitory actions are dependent on the final cytosolic concentration of buffer within the egg: > or = 1.3 mmol/L blocks ooplasmic streaming; < 1.3 mmol/L eggs segregate normally. Injection of 5,5'-dimethyl-BAPTA (KD = 0.15 micromol/L) to a final concentration of 1.5 mmol/L as a control has no effect on ooplasmic streaming. These results suggest that localized domains of elevated free cytosolic calcium are essential for ooplasmic segregation in zebrafish. Furthermore, a hypothetical model is presented linking these calcium transients to the contraction of a cortically located actin microfilament network as a possible mechanism providing the driving force for segregation.
Genes / Markers
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Orthology
Engineered Foreign Genes
Mapping