Mitochondrial DNA based diversity studies reveal distinct and substructured populations of pearlspot, (Bloch, 1790) in Indian waters.

Pearlspot () is one of the most commercially important brackish water fish species widely found along the coastal regions of peninsular India and Sri Lanka. Pearlspot is known for its tender flesh, delectable taste, culinary tourism and highyielding market value. Information on the genetic makeup of stocks/populations is extremely vital as it forms the basis for future genetic studies.

Insights on Molecular Mechanisms of Ovarian Development in Decapod Crustacea: Focus on Vitellogenesis-Stimulating Factors and Pathways.

Vitellogenesis in crustaceans is an energy-consuming process. Though the underlying mechanisms of ovarian maturation in decapod Crustacea are still unclear, evidence indicates the process to be regulated by antagonistically-acting inhibitory and stimulating factors specifically originating from X-organ/sinus gland (XO/SG) complex. Among the reported neuromediators, neuropeptides belonging to the crustacean hyperglycemic hormone (CHH)-family have been studied extensively.

Expression dynamics of solute carrier family 15 member 4 (SLC15A4) and its potential regulatory role in ovarian development of the Indian white shrimp, Penaeus indicus.

Solute carrier proteins (SLC) are essential membrane transport proteins responsible for transporting lipids, amino acids, sugars, neurotransmitters, and drugs across the biological membranes. Dysfunction of these carrier proteins may lead to an imbalance of biological mechanisms and also in the failure of the transporting pathways of several signaling neurotransmitters. In the present study, a 646 bp of a solute carrier protein (SLC15A4) was cloned and sequenced from the Indian white shrimp, Penaeus indicus.

Characterization and expression profile of farnesoic acid O-methyltransferase gene from Indian white shrimp, Penaeus indicus.

Methyl farnesoate (MF), a sesquiterpenoid synthesized in the mandibular organ, regulates many physiological processes in crustaceans including growth and reproduction. In the present study, farnesoic acid O-methyltransferase (FAMeT), the key enzyme responsible for final step conversion of farnesoic acid (FA) to methyl farnesoate (MF), was cloned and characterized from the nervous tissues of Penaeus indicus. Multiple sequence alignment, prediction of conserved domain regions, phosphorylation sites identification and phylogenetic analysis indicated that putative FAMeT fragment from P.

Sex differentiation and sex change in the protandrous black porgy, Acanthopagrus schlegeli.

Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle with a male sex differentiation at the juvenile stage and male-to-female sex change at 3 years of age. We had characterized the sex differentiation and sex change in this species by the integrative approaches of histology, endocrine and molecular genetics. The fish differentiated in gonad at the age around 4-months and the gonad further developed with a bisexual gonad for almost for 3 years and sex change at 3 year of age.

Age-dependent differential expression of genes involved in steroid signalling pathway in the brain of protandrous black porgy, Acanthopagrus schlegeli.

The mechanisms underlying brain sex differentiation in animals are poorly understood. In the present study, using black porgy, Acanthopagrus schlegeli, as primary experimental model, we investigated the temporal expression patterns of receptors for androgen (ar) and estrogen (esr1 and esr2a) in the brain during posthatching ages and analyzed them against the timing of gonadal germ cell development. We hypothesized that endogenous estrogens naturally masculinize the brain of black porgy.

Salinity effects on the expression of osmoregulatory genes in the euryhaline black porgy Acanthopagrus schlegeli.

Black porgy is a marine euryhaline species with a capacity to cope with demands in a wide range of salinities and thus is a perfect model-fish to study osmoregulatory responses to salinity-acclimated processes and their hormonal control. The present study was performed to understand the regulatory changes in hormone, hormone receptors and important osmoregulatory genes in pituitary, gill, intestine and kidney in response to acute salinity stress. Transcript levels were analyzed by quantitative real-time PCR following acute salinity challenge by direct transfer of seawater (SW) acclimatized fish to fresh water (FWBP) and vice versa (SWBP).

Dual roles of cyp19a1a in gonadal sex differentiation and development in the protandrous black porgy, Acanthopagrus schlegeli.

Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle, with male sex differentiation at the juvenile stage, a bisexual gonad during first 2 yr of life, and a male-to-female sex change (with vitellogenic oocytes) at 3 yr of age. The present study investigated the role of aromatase (cyp19a1a/Cyp19a1a) in gonadal development in this species, especially in relation to sexual differentiation and sex change. Fish of various ages were treated with estradiol (E2) or aromatase inhibitor (AI) to determine whether manipulation of the hormonal environment has an impact on these processes.

The expression of nr0b1 and nr5a4 during gonad development and sex change in protandrous black porgy fish, Acanthopagrus schlegeli.

Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle, with a mono-male sex differentiation at the juvenile stage and male-to-female sex change at 3 yr of age. We report for the first time integrative molecular data on these interesting phenomena. Sex differentiation occurred between 4 and 5 mo of age.