Short communication: Differential expression of piwi1 and piwi2 genes in tissues of tambacu and zebrafish: A possible relationship with the indeterminate muscle growth.

Fish skeletal muscle is a component of the human diet, and understanding the mechanisms that control muscle growth can contribute to improving production in this sector and benefits the human health. In this sense, fish such as tambacu can represent a valuable source for exploring muscle growth regulators due to the indeterminate muscle growth pattern. In this context, the genes responsible for the indeterminate and determinate muscle growth pattern of fish are little explored, with piwi genes being possible candidates involved with these growth patterns.

Transcriptomic insight into the hybridization mechanism of the Tambacu, a hybrid from Colossoma macropomum (Tambaqui) and Piaractus mesopotamicus (Pacu).

Interspecific hybrids are highly complex organisms, especially considering aspects related to the organization of genetic material. The diversity of possibilities created by the genetic combination between different species makes it difficult to establish a large-scale analysis methodology. An example of this complexity is Tambacu, an interspecific hybrid of Colossoma macropomum (Tambaqui) and Piaractus mesopotamicus (Pacu).

Rainbow trout slow myoblast cell culture as a model to study slow skeletal muscle, and the characterization of and families as a case study.

Muscle fibres are classified as fast, intermediate and slow. myoblast cell culture model from fast muscle is a very useful tool to study muscle growth and development; however, similar models for slow muscle do not exist. Owing to the compartmentalization of fish muscle fibres, we have developed a slow myoblast cell culture for rainbow trout ().

Prolonged fasting followed by refeeding modifies proteome profile and parvalbumin expression in the fast-twitch muscle of pacu (Piaractus mesopotamicus).

Here, we analyzed the fast-twitch muscle of juvenile Piaractus mesopotamicus (pacu) submitted to prolonged fasting (30d) and refeeding (6h, 24h, 48h and 30d). We measured the relative rate of weight and length increase (RRIlength and RRIweight), performed shotgun proteomic analysis and did Western blotting for PVALB after 30d of fasting and 30d of refeeding. We assessed the gene expression of igf-1, mafbx and pvalb after 30d of fasting and after 6h, 24h, 48h and 30d of refeeding.

The combination of resveratrol and exercise enhances muscle growth characteristics in pacu (Piaractus mesopotamicus).

Pacu is a tropical fish with important value to aquaculture. During cellular metabolism, reactive oxygen species (ROS) are produced, which can influence muscle growth. Resveratrol is an effective antioxidant that scavenges ROS and can modulate physical performance preventing oxidative stress.

Association of CAST2, HSP90AA1, DNAJA1 and HSPB1 genes with meat tenderness in Nellore cattle.

The objective of this study was to evaluate the association of expression of CAPN1, CAPN2, CAST, HSP90AA1, DNAJA1 and HSPB1 genes with meat tenderness in Nellore cattle. Three experimental groups were selected by shear force (SF): moderately tender (SF=34.3±5.

Osteoglycin inhibition by microRNA miR-155 impairs myogenesis.

Skeletal myogenesis is a regulated process in which mononucleated cells, the myoblasts, undergo proliferation and differentiation. Upon differentiation, the cells align with each other, and subsequently fuse to form terminally differentiated multinucleated myotubes. Previous reports have identified the protein osteoglycin (Ogn) as an important component of the skeletal muscle secretome, which is expressed differentially during muscle development.

Food restriction increase the expression of mTORC1 complex genes in the skeletal muscle of juvenile pacu (Piaractus mesopotamicus).

Skeletal muscle is capable of phenotypic adaptation to environmental factors, such as nutrient availability, by altering the balance between muscle catabolism and anabolism that in turn coordinates muscle growth. Small noncoding RNAs, known as microRNAs (miRNAs), repress the expression of target mRNAs, and many studies have demonstrated that miRNAs regulate the mRNAs of catabolic and anabolic genes. We evaluated muscle morphology, gene expression of components involved in catabolism, anabolism and energetic metabolism and miRNAs expression in both the fast and slow muscle of juvenile pacu (Piaractus mesopotamicus) during food restriction and refeeding.

Differential microRNA Expression in Fast- and Slow-Twitch Skeletal Muscle of Piaractus mesopotamicus during Growth.

Pacu (Piaractus mesopotamicus) is a Brazilian fish with a high economic value in pisciculture due to its rusticity and fast growth. Postnatal growth of skeletal muscle in fish occurs by hyperplasia and/or hypertrophy, processes that are dependent on the proliferation and differentiation of myoblasts. A class of small noncoding RNAs, known as microRNAs (miRNAs), represses the expression of target mRNAs, and many studies have demonstrated that miR-1, miR-133, miR-206 and miR-499 regulate different processes in skeletal muscle through the mRNA silencing of hdac4 (histone deacetylase 4), srf (serum response factor), pax7 (paired box 7) and sox6 ((sex determining region Y)-box 6), respectively.