The purpose of this project is to identify genes positively and negatively regulated by signaling molecules that belongs to the TGFbeta superfamily.

Vegetal and lateral views of 110-cell stage embryos probed for Ci-actin expression. Embryos were injected with CiMDFb mRNA into eggs, which were then fertilized and examined for muscle-specific gene activity at 110-cell stage. In the injected embryos we can see an increase in the level of actin expression. These pictures shows expression of actin in the muscle (as in control) and in all the B-cell lineage that give rise to endoderm, mesenchyme and notochord.

Effects of knockdown of Ci-Tbx6b on the expression of muscle protein genes. Fertilized eggs were injected with Tbx6b and the expression of Ci-MA was examined at the 110-cell stage.

Effects of knockdown of Ci-Tbx6c on the expression of muscle protein genes. Fertilized eggs were injected with Tbx6c and the expression of Ci-MA was examined at the 110-cell stage.

Vegetal view of a mid gastrula stage embryo probed for Ci-Actin expression following the injection of a DAPT. Cell division was blocked by cytochalasin B, gene expression profile corresponds to the stage observed.
Graph shows the percentage of embryo with ectopic, strong or weak Ci-actin expression.'Weak' means at least one cell with downregulated expression, 'strong' means at least one A-line precursor cell with strong expression.

Original Annotation : Ci-Actin expression was affected by the inhibition of Delta2/Notch signaling, there is a loss of expression in A9.32 cell pair.

Vegetal view of a mid gastrula stage embryo probed for Ci-Actin expression, following the injection of a Delta2-MO. Cell division was blocked by cytochalasin B, gene expression profile corresponds to the stage observed.
Graph shows the percentage of embryo with ectopic, strong or weak Ci-actin expression.'Weak' means at least one cell with downregulated expression, 'strong' means at least one A-line precursor cell with strong expression.

Original annotation : Ci-Actin expression was affected by the inhibition of Delta2/Notch signaling, there is a loss of expression in A9.32 cell pair.

Graph shows the percentage of embryo with ectopic, strong or weak Ci-actin expression following the injection of a dominant negative of Delta2, DnDel2. Cell division was blocked by cytochalasin B, gene expression profile corresponds to the stage observed. 'Weak' means at least one cell with downregulated expression, 'strong' means at least one A-line precursor cell with strong expression.

Original Annotation : Ci-Actin expression was affected by the inhibition of Delta2/Notch signaling, there is a loss of expression in A9.32 cell pair.

Vegetal view of a early neurula stage embryo probed for Ci-Actin expression following egg micro-injection of a Nodal-MO. Nodal signalling is inhibited. Control sibling embryo shows the wild type pattern of the gene and a control cleaving embryos for Ci-OTX expression. Cell division was blocked by cytochalasin B.

expression is lost from the secondary muscle lineage and kept in the primary muscle lineage.

Vegetal view of a early neurula stage embryo probed for Ci-muscle Actin expression following inhibition of nodal receptor type I by SB431542. Nodal signalling is inhibited. Control sibling embryo shows the wild type pattern of the gene and a control cleaving embryos for Ci-OTX expression. Cell division was blocked by cytochalasin B.

Expression is lost from the secondary muscle lineage and kept in the primary muscle lineage.

Injection of Ci-Tbx6b mRNA causes an expression of Ci-MA (Muscle Actin) in the whole embryo contrary to the control where Ci-MA is only expressed in tail-muscle cells.

Injection of Ci-Tbx6b MO causes a light expression of Ci-MA (Muscle Actin) in the whole embryo, contrary to the control where Ci-MA is only expressed in tail-muscle cells. Note that a small pack of primary muscle lineage cells keeps a normal expression of Ci-MA.

Injection of Ci-Tbx6c mRNA causes an expression of Ci-MA (Muscle Actin) in the whole embryo contrary to the control where Ci-MA is only expressed in tail-muscle cells.

Injection of Ci-Tbx6c MO strongly reduces and disturbs the expression of Ci-MA (Muscle Actin) in tail-muscle cells.

Effects of knockdown of Ci-Tbx6b on the expression of muscle protein genes. Fertilized eggs were injected with Ci-Tbx6b MO. Expression was examined at the mid tailbud stage. Embryos were cleavage arrested at the 110-cell stage by injection of cytochalasin B.

Effects of knockdown of Ci-Tbx6c on the expression of muscle protein genes. Fertilized eggs were injected with Ci-Tbx6c MO. Expression was examined at the mid tailbud stage. Embryos were cleavage arrested at the 110-cell stage by injection of cytochalasin B.

Effects of simultaneous knockdown of Ci-Tbx6b/Ci-Tbx6c on the expression of muscle protein genes. The expression of Ci-MA was examined at the tailbud stage.

Effects of simultaneous knockdown of Ci-Tbx6b/Ci-Tbx6c/Ci-ZicL on the expression of muscle protein genes. The expression of Ci-MA was examined at the tailbud stage.

Lateral and dorsal views of a late tailbud stage embryo. These embryos were injected at egg stage with Ci-MRF mRNA and probed for Ci-Actin expression at late tailbud stage. The embryo did not develop normally and Ci-Actin is expressed in three-quarters of the cells.

Lateral pole view of late tailbud stage embryos probed for Ci-Actin expression in which Ci-MRF was blocked by Ci-MRF-MO1640. These pictures show an abnormal tail muscle formation.