RESUMEN
Seahorses have a specialized morphology that includes a toothless tubular mouth, a body covered with bony plates, a male brood pouch, and the absence of caudal and pelvic fins. Here we report the sequencing and de novo assembly of the genome of the tiger tail seahorse, Hippocampus comes. Comparative genomic analysis identifies higher protein and nucleotide evolutionary rates in H. comes compared with other teleost fish genomes. We identified an astacin metalloprotease gene family that has undergone expansion and is highly expressed in the male brood pouch. We also find that the H. comes genome lacks enamel matrix protein-coding proline/glutamine-rich secretory calcium-binding phosphoprotein genes, which might have led to the loss of mineralized teeth. tbx4, a regulator of hindlimb development, is also not found in H. comes genome. Knockout of tbx4 in zebrafish showed a 'pelvic fin-loss' phenotype similar to that of seahorses.
Asunto(s)
Evolución Biológica , Proteínas de Peces/genética , Genoma/genética , Smegmamorpha/anatomía & histología , Smegmamorpha/genética , Aletas de Animales/anatomía & histología , Aletas de Animales/metabolismo , Animales , Secuencia Conservada/genética , Proteínas de Peces/deficiencia , Eliminación de Gen , Genómica , Miembro Posterior/anatomía & histología , Miembro Posterior/metabolismo , Masculino , Anotación de Secuencia Molecular , Familia de Multigenes/genética , Tasa de Mutación , Filogenia , Reproducción/fisiología , Proteínas de Dominio T Box/deficiencia , Proteínas de Dominio T Box/genética , Factores de Tiempo , Proteínas de Pez Cebra/deficiencia , Proteínas de Pez Cebra/genéticaRESUMEN
The iconic phenotype of seadragons includes leaf-like appendages, a toothless tubular mouth, and male pregnancy involving incubation of fertilized eggs on an open "brood patch." We de novo-sequenced male and female genomes of the common seadragon (Phyllopteryx taeniolatus) and its closely related species, the alligator pipefish (Syngnathoides biaculeatus). Transcription profiles from an evolutionary novelty, the leaf-like appendages, show that a set of genes typically involved in fin development have been co-opted as well as an enrichment of transcripts for potential tissue repair and immune defense genes. The zebrafish mutants for scpp5, which is lost in all syngnathids, were found to lack or have deformed pharyngeal teeth, supporting the hypothesis that the loss of scpp5 has contributed to the loss of teeth in syngnathids. A putative sex-determining locus encoding a male-specific amhr2y gene shared by common seadragon and alligator pipefish was identified.
Asunto(s)
Smegmamorpha , Pez Cebra , Animales , Evolución Biológica , Femenino , Genoma , Masculino , Fenotipo , Pez Cebra/genéticaRESUMEN
Syngnathids (seahorses, pipefishes and seadragons) exhibit an array of morphological innovations including loss of pelvic fins, a toothless tubular mouth and male pregnancy. They comprise two subfamilies: Syngnathinae and Nerophinae. Genomes of three Syngnathinae members have been analyzed previously. In this study, we have sequenced the genome of a Nerophinae member, the Manado pipefish (Microphis manadensis), which has a semi-enclosed brood pouch. Comparative genomic analysis revealed that the molecular evolutionary rate of the four syngnathids is higher than that of other teleosts. The loss of all but one P/Q-rich SCPP gene in the syngnathids suggests a role for the lost genes in dentin and enameloid formation in teleosts. Genome-wide comparison identified a set of 118 genes with parallel identical amino acid substitutions in syngnathids and placental mammals. Association of some of these genes with placental and embryonic development in mammals suggests a role for them in syngnathid pregnancy.
RESUMEN
Ubiquitin-conjugating protein 9 (Ubc9), the sole enzyme for sumoylation, plays critical roles in many physiological functions, such as DNA damage repair and genome integrity. Its overexpression led to poor prognosis and drug resistance in tumor chemotherapy. However, the underlying mechanism by which Ubc9 promotes tumor progress and influences the susceptibility to antitumor agents remains elusive. In this study, we used nine antitumor agents with distinct actions to explore Ubc9-mediated resistance in human breast carcinoma MCF-7 cells. Increase of susceptibility, respectively, to boningmycin, hydroxycamptothecine, cis-dichlorodiamineplatinum, 5-fluorouracil, vepeside and gemcitabine, but not for doxorubicin, vincristine and norcantharidin, was observed after the knockdown of Ubc9 protein level with RNA interference. Reduction of bleomycin hydrolase and poly(ADP-ribose) polymerase-1 levels after knockdown of Ubc9 suggests their contribution to Ubc9-mediated drug resistance. This is the first report on the sensitivity to hydroxycamptothecine, cis-dichlorodiamineplatinum and gemcitabine that increased after knockdown of bleomycin hydrolase at protein level. In conclusion, Ubc9 plays different roles of action in antitumor agents in chemotherapy. The process requires bleomycin hydrolase and poly(ADP-ribose) polymerase-1. The results are beneficial to deeply understanding of Ubc9 functions and for precise prediction of chemotherapy outcomes in tumors.