Expression of cell adhesion molecules in the normal and T3 blocked development of the tadpole's kidney of Bufo arenarum (Amphibian, Anuran, Bufonidae)

Abstract

Cell adhesion molecules act as signal transducers from the extracellular environment to the cytoskeleton and the nucleus and consequently induce changes in the expression pattern of structural proteins. In this study, we showed the effect of thyroid hormone (TH) inhibition and arrest of metamorphosis on the expression of E-cadherin, -and -catenin in the developing kidney of Bufo arenarum. Cell adhesion molecules have selective temporal and spatial expression during development suggesting a specific role in nephrogenesis. In order to study mechanisms controlling the expression of adhesion molecules during renal development, we blocked the B. arenarum metamorphosis with a goitrogenic substance that blocks TH synthesis. E-cadherin expression in the proximal tubules is independent of thyroid control. However, the blockage of TH synthesis causes up-regulation of E-cadherin in the collecting ducts, the distal tubules and the glomeruli. The expression of -and -catenin in the collecting ducts, the distal tubules, the glomeruli and the mesonephric mesenchyme is independent of TH. TH blockage causes up-regulation of -and -catenin in the proximal tubules. In contrast to E-cadherin, the expression of the desmosomal cadherin desmoglein 1 (Dsg-1) is absent in the control of the larvae kidney during metamorphosis and is expressed in some interstitial cells in the KClO 4 treated larvae. According to this work, the Dsg-1 expression is down-regulated by TH. We demonstrated that the expression of E-cadherin, Dsg-1, -catenin and -catenin are differentially affected by TH levels, suggesting a hormone-dependent role of these proteins in the B. arenarum renal metamorphosis.Keywords: catenins, cadherins, metamorphosis, amphibians. Expressão das moléculas de adesão celular no desenvolvimento normale com a inibição do hormônio tireoidea do rim nas larvas do Bufo arenarum (Amphibia, Anura, Bufonidae) ResumoMoléculas de adesão celular atuam como tradutores do ambiente extracelular para o citoesqueleto e o núcleo e, conseqüentemente, induzindo mudanças no padrão da expressão das proteínas estruturais. Neste estudo, observamos os efeitos da inibição do hormônio tireóidea (TH) e detenção da metamorfose na expressão da E-caderina, -e -catenina no desenvolvimento do rim do Bufo arenarum. As moléculas de adesão celular durante o desenvolvimento têm uma expressão temporal e espacial seletiva, sugerindo um papel específico na nefrogênese. Com o propósito de estudar os mecanismos de controle da expressão das moléculas de adesão durante o desenvolvimento renal, bloqueou-se a metamorfose do B. arenarum com uma substancia goitrogênica que bloqueia a síntese de TH. A expressão da E-caderina nos tubos proximais é independente do controle da tireóide. Entretanto, o bloqueio da síntese de TH provoca uma sobre elevação da E-caderina nos dutos coletores, nos tubos distais e nos glomérulos. A expressão da -e -catenina nos dutos coletores, nos tubos distais, nos glomérulos e no mesênquima mesonéfrico é independente da TH. O bloqueio da TH causa uma so...

In Vivo Study of Epithelial Adhesion via E-Cadherin-β- and α- Catenin-small GTP-Binding Proteins under T3 Regulation

“…The results of the current work confirm our own assumptions and those reported by other authors, and allow to deepen the molecular mechanisms involved in dynamic regulation of amphibian gastrointestinal epithelial cell-cell adhesive contacts in physiological conditions [17,2] allowing to understand some pathological behaviors [56].Thus, as early as within 24 h post T3-treatment, E-cadherin, β-and α-catenin significantlly increase their expression. While intercellular distances of AJs and Dms increase, just the Dms number decrease.…”

“…Phosphorylation level of epithelial AJs molecules also causes deep changes in the expression pattern of E-cadherin and β-catenin during epithelial development [2]. Interesting, cell-cell contacts mediated by E-cadherin, β-and α-catenin change in response to extracellular TH levels through epithelia development, conducting tissular remodeling and adult cell contact strengthening [2,4,[15][16][17].…”

Total sialic acid profile in regressing and remodelling organs during the metamorphosis of marsh frog (Pelophylax ridibundus Pallas 1771)

“…The high content of PSA enables cell migration, axon outgrowth and formation of neural circuits by providing more plasticity in cell interaction . Besides, the presence of NCAM expression was also reported in adult Xenopus liver and intestine and in developing Bufo arenarum kidney . Therefore, cell adhesion molecules play significant regulatory roles in morphogenesis and histogenesis and sialic acid one of the important structural residue of NCAM.…”

“…34 Besides, the presence of NCAM expression was also reported in adult Xenopus liver and intestine 7 and in developing Bufo arenarum kidney. 15 Therefore, cell adhesion molecules play significant regulatory roles in morphogenesis and histogenesis and sialic acid one of the important structural residue of NCAM. Although there is no direct evidence and not enough information on the role of sialic acid in larval intestinal development, by considering our data and available knowledge, we can state that changes in the sialic acid level can directly reflect the proliferative process and that sialic acid can play a role in the proliferation of the new-generation cell types and morphogenesis of the adult-type digestive tract during larval intestinal development.…”

E-cadherin roles in animal biology: A perspective on thyroid hormone-influence

“…Among them, cell-type dependent proliferation and differentiation both in mammalian skin [101, 113, 164, 195] and gut [158, 178], as in anuran kidney [84], skin [86] and gut [55, 56, 85]. These effects are regulated by phosphorilation levels of several partner proteins [86] and modulation of gen expression [56, 85].…”