Department of Biology, Indian Institute of Science Education and Research-Pune (IISER-Pune), Dr Homi Bhabha Road, Pashan, Pune 411008, India.
Department of Biology, Indian Institute of Science Education and Research-Pune (IISER-Pune), Dr Homi Bhabha Road, Pashan, Pune 411008, India.
Cells Dev. 2021 Jun;166:203684. doi: 10.1016/j.cdev.2021.203684. Epub 2021 Apr 28.
Scales are skin appendages in fishes that evolutionarily predate feathers in birds and hair in mammals. Zebrafish scales are dermal in origin and develop during metamorphosis. Understanding regulation of scale development in zebrafish offers an exciting possibility of unraveling how the mechanisms of skin appendage formation evolved in lower vertebrates and whether these mechanisms remained conserved in birds and mammals. Here we have investigated the expression and function of twist 2/dermo1 gene - known for its function in feather and hair formation - in scale development and regeneration. We show that of the four zebrafish twist paralogues, twist2/dermo1 and twist3 are expressed in the scale forming cells during scale development. Their expression is also upregulated during scale regeneration. Our knockout analysis reveals that twist2/dermo1 gene functions in the maintenance of the scale shape and organization during development as well as regeneration. We further show that the expression of twist2/dermo1 and twist3 is regulated by Wnt signaling. Our results demonstrate that the function of twist2/dermo1 in skin appendage formation, presumably under regulation of Wnt signaling, originated during evolution of basal vertebrates.
鳞片是鱼类的皮肤附属物，其在进化上早于鸟类的羽毛和哺乳动物的毛发。斑马鱼的鳞片起源于真皮，并在变态期间发育。了解斑马鱼鳞片发育的调控机制，为揭示皮肤附属物形成的机制在低等脊椎动物中是如何进化的，以及这些机制在鸟类和哺乳动物中是否仍然保守，提供了一个令人兴奋的可能性。在这里，我们研究了 twist 2/dermo1 基因的表达和功能——该基因已知在羽毛和毛发形成中起作用——在鳞片发育和再生中的作用。我们发现，在四个斑马鱼 twist 同源物中， twist2/dermo1 和 twist3 在鳞片形成细胞中表达，在鳞片再生过程中表达也上调。我们的敲除分析表明， twist2/dermo1 基因在发育和再生过程中维持鳞片的形状和组织。我们进一步表明， twist2/dermo1 和 twist3 的表达受 Wnt 信号的调节。我们的结果表明， twist2/dermo1 在皮肤附属物形成中的作用（推测受 Wnt 信号的调节）在基础脊椎动物的进化过程中起源。
