MicroRNA Transcriptomes Reveal Prevalence of Rare and Species-Specific Arm Switching Events During Zebrafish Ontogenesis.

In metazoans, microRNAs (miRNAs) are essential regulators of gene expression, affecting critical cellular processes from differentiation and proliferation, to homeostasis. During miRNA biogenesis, the miRNA strand that loads onto the RNA-induced Silencing Complex (RISC) can vary, leading to changes in gene targeting and modulation of biological pathways. To investigate the impact of these "arm switching" events on gene regulation, we analyzed a diverse range of tissues and developmental stages in zebrafish by comparing 5p and 3p arms accumulation dynamics between embryonic developmental stages, adult tissues, and sexes.

A83-01 and DMH1 effects in the zebrafish spermatogonial niche: Unraveling the roles of TGF-β and BMP signaling in the Fsh-mediated spermatogonial fate.

Transforming growth factor-β (TGF-β) and bone morphogenetic protein (BMP) signaling has fundamental roles in the regulation of the stem cell niche for both embryonic and adult stem cells. In zebrafish, male germ stem cell niche is regulated by follicle-stimulating hormone (Fsh) through different members of the TGF-β superfamily. On the other hand, the specific roles of TGF-β and BMP signaling pathways are unknown in the zebrafish male germ stem cell niche.

DNA barcodes identify marine fishes of São Paulo State, Brazil.

Anthropogenic impacts are an increasing threat to the diversity of fishes, especially in areas around large urban centres, and many effective conservation actions depend on accurate species identification. Considering the utility of DNA barcoding as a global system for species identification and discovery, this study aims to assemble a DNA barcode reference sequence library for marine fishes from the coastal region of São Paulo State, Brazil. The standard 652 bp 'barcode' fragment of the cytochrome c oxidase subunit I (COI) gene was PCR amplified and bidirectionally sequenced from 678 individuals belonging to 135 species.