Follicular atresia is the mechanism by which the oocyte contents are degraded during oogenesis in response to stress conditions, allowing the energetic resources stored in the developing oocytes to be reallocated to optimize female fitness. Autophagy is a conserved intracellular degradation pathway where double-membrane vesicles are formed around target organelles leading to their degradation after lysosome fusion. The autophagy-related protein 8 (ATG8) is conjugated to the autophagic membrane and has a key role in the elongation and closure of the autophagosome. Here we identified one single isoform of ATG8 in the genome of the insect vector of Chagas Disease Rhodnius prolixus (RpATG8) and found that it is highly expressed in the ovary during vitellogenesis. Accordingly, autophagosomes were detected in the vitellogenic oocytes, as seen by immunoblotting and electron microscopy. To test if autophagosomes were important for follicular atresia, we silenced RpATG8 and elicited atresia in vitellogenic females by Zymosan-A injections. We found that silenced females were still able to trigger the same levels of follicle atresia, and that their atretic oocytes presented a characteristic morphology, with accumulated brown aggregates. Regardless of the difference in morphology, RpATG8-silenced atretic oocytes presented the same levels of protein, TAG and PolyP, as detected in control atretic oocytes, as well as the same levels of acidification of the yolk organelles. Because follicular atresia has the ultimate goal of restoring female fitness, we tested if RpATG8-silenced atresia would result in female physiology and behavior changes. Under insectarium conditions, we found that atresia-induced control and RpATG8-silenced females present no changes in blood meal digestion, survival, oviposition, TAG content in the fat body, haemolymph amino acid levels and overall locomotor activity. Altogether, we found that autophagosomes are formed during oogenesis and that the silencing of RpATG8 impairs autophagosome biogenesis in the PLOS Neglected Tropical Diseases | https://doi.

Elevation of parathyroid hormone, low dietary calcium intake, and vitamin D plasma insufficiency without BMD reduction occurred after RYGBP. Patients who underwent RYGBP had adequate lipid profiles but inadequate intake protein, polyunsaturated fatty acids, fiber, and iron. Vitamin D deficiency may occur in the late postoperative period.

In insects, the last stage of the oogenesis is the choriogenesis, a process where the multiple layers of the chorion are synthesized, secreted, and deposited in the surface of the oocytes by the follicle cells. The chorion is an extracellular matrix that serves as a highly specialized protective shield for the embryo, being crucial to impair water loss and to allow gas exchange throughout development. The E2-like enzyme ATG3 (autophagy related gene 3) is known for its canonical function in the autophagy pathway, in the conjugation of the ubiquitin-like ATG8/LC3 to the membranes of autophagosomes. Although the ATGs were originally described and annotated as genes related to autophagy, additional functions have been attributed to various of these genes. Here, we found that Rhodnius prolixus ATG3 is highly expressed in the ovaries of the adult vitellogenic females. Parental RNAi depletion of ATG3 resulted in a 15% decrease in the oviposition rates of depleted females and in the generation of unviable eggs. ATG3-depleted eggs are small and present one specific phenotype of altered chorion ultrastructure, observed by high resolution scanning electron microscopy. The amounts of the major chorion proteins Rp30, Rp45, Rp100, and Rp200 were decreased in the ATG3-depleted chorions, as well as the readings for dityrosine cross-linking and sulfur, detected by fluorescence emission under ultraviolet excitation and X-ray elemental detection and mapping. Altogether, we found that ATG3 is important for the proper chorion biogenesis and, therefore, crucial for this vector reproduction.

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