MicroRNAs, potential coordinators of the insulin pathway and the aging process of Apis mellifera
Fábio Oliveira Barbin, Fábio Oliveira Barbin , Flávia Cristina de Paula Freitas , Zilá Luz Paulino Simões
Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, Brazil; Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, Brazil ; Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, Brazil ; Departamento de Genética, Universidade de São Paulo, Ribeirão Preto, Brazil
Aging is a time-progressive decline of all intrinsic physiological functions. It is a natural process present in all organisms and a resultant of genetic and environmental interactions. An important step of the metabolism is affected by the senescence, the insulin-signaling pathway. In Apis mellifera during the adult phase occurs a process related to aging: the functions assumed by young bees are different from the observed in old bees. That is, the worker perform a progressive task program known as age polyethism that includes also multiple functions inside the colony. During young phase, worker bees known as nurses organize the colony and feed the larvae, but from the second week on, the workers start to perform activities outside the nest, searching for pollen and nectar, then called foragers. However, a singular character, the phenotypic plasticity, permits changes in this program. Age polyethism has reflexes not only on the physiology of these bees but also on the behavior and specific metabolic pathways, such as the insulin-signaling pathway and its molecule regulators. The microRNAs are one of these molecules. They participate in many systemic signaling pathways, including the insulin. However, there are still unanswered questions: how could microRNAs, interacting with insulin and ecdysteroid pathways, interfere with the maturation and aging of honeybees? Through qRT-PCR experiments, we analyzed the relative transcription of related genes throughout the adult life of bees. The insulin pathway plays an important role in the aging process and A. mellifera is a good model for the study. So as we propose in this project to define the participation of the microRNAs, miR -8, miR-14 and miR-34, in the regulation of the studied genes, Pten, DOR, Pi3K, chico and Eip74EF that are modulated in the aging process of many organisms. Altogether, our results would provide new elements for a better understanding of the development and aging process in bees and other insects.