About the Authors
Centro Andaluz de Biología del Desarrollo, CSIC/Universidad Pablo de Olavide, Sevilla, Spain
Centro de Biología Molecular Severo Ochoa, CSIC/Universidad Autónoma de Madrid, Madrid, Spain
The authors have declared that no competing interests exist.
The author(s) have made the following declarations about their contributions: Conceived and designed the experiments: PR-R IG AG-R. Performed the experiments: PR-R AG-R. Analyzed the data: PR-R AG-R. Contributed reagents/materials/analysis tools: PR-R IG AG-R. Wrote the paper: PR-R IG AG-R.