Characterization of vasa homolog in a neotropical catfish, Jundiá ( Rhamdia quelen ): Molecular cloning and expression analysis during embryonic and larval development

Abstract

We have characterized the full-length vasa cDNA from Jundiá, Rhamdia quelen (Heptapteridae, Siluriformes). vasa encodes a member of the DEAD-box protein family of ATP-dependent RNA helicases. This protein is highly conserved among different organisms and its role is associated with RNA metabolism. In the majority of the investigated species, vasa is restricted to the germ cell lineage and its expression has been used to study germline development in many organisms, including fish. The deduced R. quelen vasa amino acid sequence displayed high similarity with Vasa protein sequences from other organisms, and did not cluster with PL10 or P68 DEAD-box protein subfamilies. We also reported that there is no other isoform for vasa mRNA in R. quelen gonads. Expression analysis by RT-PCR and qPCR showed vasa transcripts exclusively expressed in the germ cells of R. quelen gonads. R. quelen vasa mRNA was maternally inherited, and was detected in the migrating primordial germ cells (PGCs) until 264 h post-fertilization during embryonic and larval development. This work has characterized for the first time the full-length R. quelen vasa cDNA, and describes its expression patterns during R. quelen embryonic and larval development. Our results will contribute to the basic reproductive biology of this native species, and will support studies using vasa as a germ cell marker in different biotechnological studies, such as germ cell transplantation.

Primordial germ cells identification and traceability during the initial development of the Siluriformes fish Pseudopimelodus mangurus.

“…The signals obtained from the P. mangurus nanos3 probes correspond topographically to the migratory patterns of the PGC reported in other sh species ( Otani et al, 2002;Saito et al, 2004;Fujimoto et al, 2006;Ricci et al, 2018). Therefore, the results suggest that the nano3 positive cells correspond to P. mangurus PGCs and the description of the migratory route is accurate.…”

“…The identi cation and characterization of germline marker genes are essential for knowing the migration route, gonad formation, and sexual differentiation is considered a prerequisite for establishing reproductive biotechniques such as germ cell transplantation (Ricci et al, 2018). Some germ cell marker genes have already been identi ed, the vasa gene being the most studied and widely used in sh species (Knaut et al, 2000;Li et al, 2009;Raz, 2003;Shinomiya et al, 2000;Yoon et al, 1997;Yoshizaki et al, 2000).…”

Histological characterization of the maturation stages of the ovarian follicles of the goldfish Carassius auratus (Linnaeus, 1758)

“…and Empetrichthys latos (Uribe et al, 2012), but differ from the large thread-like basophilic bodies of the swordfish (Corriero et al, 2004) and rainbow trout (Gülsoy, 2009), and the round basophilic ones of the catfish Jundiá (Ricci et al, 2018). The significance of such differences is unclear, but we argue that one cause for the variance in aspect is the corpuscle disintegration over time.…”

“…Despite seldom illustrated, the structure of the Balbiani corpuscles does not seem universal in fish. Those of goldfish resemble images from zebrafish (Marlow & Mullins, 2008) and goodeids Crenichthys baileyi and Empetrichthys latos (Uribe et al., 2012), but differ from the large thread‐like basophilic bodies of the swordfish (Corriero et al, 2004) and rainbow trout (Gülsoy, 2009), and the round basophilic ones of the catfish Jundiá (Ricci et al., 2018). The significance of such differences is unclear, but we argue that one cause for the variance in aspect is the corpuscle disintegration over time.…”

Cloning Method for Stress-Resistant Gene of Conringia planisiliqua under Drought Stress

“…After quickfreezing process with liquid nitrogen, they were stored in a refrigerator at 70°C. After that, RNA was extracted and purified with Trizol plant extraction kit of Tiangen, based on the instructions [14]. DNA was removed from RNA by DNase I kit.…”