Month: September 2022

EYE MIGRATION AND HORMONES. "Treatment of pre-metamorphic larvae with triiodothyronine (T3) induced bilaterally symmetrical condensation of both frontal bones and symmetrical resorption of both SBs. Eye migration in these larvae is inhibited." https://lnkd.in/d9EMwRb View in LinkedIn

THYROXIN MORPHS. "Interestingly, the occurrence of bilaterally symmetrical flatfish variants in aquaculture has been reported, and symmetrical variants appear similar to symmetrical spotted halibut (Verasper variegatus) juveniles that were artificially produced by treating early pre-metamorphic larvae with thyroxin." https://lnkd.in/d9EMwRb View in LinkedIn

THYROID HORMONE RECEPTORS "are expressed in cartilage and presumptive osteoblasts of Japanese flounder larvae, and asymmetric sensitivity to thyroid hormone in flatfish could, in principle, be regulated by differential expression of thyroid hormone receptor levels or isoforms, transcriptional coregulators, or types I, II or III deiodinase activity." https://lnkd.in/d9EMwRb View in LinkedIn

ACTING AS TRANSCRIPTION FACTORS. "The endocrine system and in particular the thyroid hormones (THs), thyroxin (T4) and triiodothyronine (T3), play a central role in vertebrate metamorphosis acting as transcription factors (TFs) when they bind to their receptors." https://lnkd.in/du68ipH View in LinkedIn

GENE REGULATION. "Thyroid hormone regulates a wide range of genes after its activation from the prohormone, thyroxine (T4), to the active form, triiodothyronine (T3). The signaling pathway is complex and highly regulated due to the expression of cell and tissue-specific thyroid hormone transporters, multiple thyroid hormone receptor (TR) isoforms, and interactions with corepressors and coactivators." https://lnkd.in/dcWUepm View in LinkedIn

THYROID HORMONE DISRUPTERS. "Chemical disruption of the thyroid axis using thiourea or methimazole (MMI) delays or stops stomach development in the Japanese flounder (Paralichthys olivaceus) and otolith mineralization in the Southern flounder (Paralichthys lethostigma). The importance of thyroid hormones during metamorphosis is further emphasized in other flatfish species where they have been shown to be important for the maturation of the muscle, stomach and skin." https://lnkd.in/du68ipH View in LinkedIn

GENE IMPACT. "The working hypothesis of the present study is that since thyroid hormones exert their action by binding to thyroid receptors that are ligand activated thyroid hormones the overt change in flatfish during metamorphosis will be preceded by significant modifications in the transcriptome of responsive tissues.” https://lnkd.in/du68ipH View in LinkedIn

PLETHORA OF GENES IMPACTED. "Overall, 135 putative thyroid hormones-responsive genes were identified in the skin, GI-tract and head transcriptome, which included transcription factors, genes involved in DNA replication, cell proliferation, cell growth and differentiation and collagen synthesis and degradation. The skin transcriptome contained 113 putative thyroid hormones-responsive genes that mainly corresponded to structural proteins, proteases, actins, transmembrane proteins, and several membrane transport proteins of the solute carrier group." https://lnkd.in/du68ipH View in LinkedIn

MASSIVE UPREGULATION. "Pairwise comparisons of the juvenile transcriptome with stage specific transcriptomes revealed a high number of DE transcripts (>8,000/stage), with the majority highly up-regulated in the juvenile stage. ours is the first next generation sequencing study analyzing individual tissues and larvae of a metamorphosing flatfish." A remarkable study showing the power of modern genetics. https://lnkd.in/du68ipH View in LinkedIn

NODAL MOLECULE. "Developmental biologists have long been fascinated by the prominent internal asymmetries of outwardly symmetric animals, a fascination piqued in the mid-1990's by the discovery of the transient, unilateral expression of the Nodal signaling molecule in the left lateral plate mesoderm. This discovery quickly opened the door for the dissection of the genetic pathways that distinguish cells on the left side of an organism from those on its right side." https://lnkd.in/d2sKgHB View in LinkedIn