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In bees from genus Melipona, differential feeding is not enough to fully explain female polyphenism. In these bees, there is a hypothesis that in addition to the environmental component (food), a genetic component is also involved in caste differentiation. This mechanism has not yet been fully elucidated and may involve epigenetic and metabolic regulation. Here, we verified that the genes encoding histone deacetylases HDAC1 and HDAC4 and histone acetyltransferase KAT2A were expressed at all stages of Melipona scutellaris, with fluctuations between developmental stages and castes. In larvae, the HDAC genes showed the same profile of Juvenile Hormone titers—previous reported—whereas the HAT gene exhibited the opposite profile. We also investigated the larvae and larval food metabolomes, but we did not identify the putative queen-fate inducing compounds, geraniol and 10-hydroxy-2E-decenoic acid (10HDA). Finally, we demonstrated that the histone deacetylase inhibitor 10HDA—the major lipid component of royal jelly and hence a putative regulator of honeybee caste differentiation—was unable to promote differentiation in queens in Melipona scutellaris. Our results suggest that epigenetic and hormonal regulations may act synergistically to drive caste differentiation in Melipona and that 10HDA is not a caste-differentiation factor in Melipona scutellaris.

The prostate development has an important postnatal period where cell proliferation begins at the first days after birth and is related to gland growth and ramification. Any metabolic and/or hormonal changes occurring during the postnatal period can interfere with prostate branching. Hyperglycemia is a common condition in low weight preterm babies at neonatal period and also a disorder found in the offspring of obese mothers. Thus, this study aimed to investigate the in vitro effects of a glucose-rich environment during prostate postnatal development. Wistar rats prostate were removed at birth and cultured for 1, 2 and 3 days in DMEM under normal (5.5mM) or elevated (7 and 25mM) glucose concentrations. Samples were processed for morphological analysis, PCNA and smooth muscle α-actin immunohistochemistry, evaluation of active caspase-3, ERK1/2 and Wnt5a gene expression. High glucose concentrations reduced the number of prostatic buds and proliferating cells. The natural increase in smooth muscle cells and collagen deposition observed in control prostates during the first 3 days of development was reduced by elevated glucose concentrations. The amount of active caspase-3 was higher in prostates incubated at 7mM and TGF-β levels also increased sharply after both glucose concentrations. Additionally, high glucose environment decreased ERK 1/ 2 activation and increased Wnt5a expression. These data show that high levels of glucose during the first postnatal days affected prostate development by inhibiting cell proliferation which impairs bud branching and this was associated with anti-proliferative signals such as decreased ERK1/2 activation and increased Wnt5a expression.

"Embaralhando Mendel e suas leis" é um jogo facilitador da aprendizagem das leis de Mendel, voltado aos alunos do ensino médio. No desenvolvimento da atividade, importantes conceitos de Genética são abordados, tais como segregação independente, formação de gametas, fecundação, genótipo, fenótipo e transmissão de características genéticas. Pretende-se por meio desse jogo desenvolver uma atividade participativa, dinâmica e integradora, que mistura conteúdo didático, competitividade e atenção.