Project description:Cryoprotection is of interest in many fields of research, necessitating a greater understanding of different cryoprotective agents. Antifreeze proteins have been identified that have the ability to confer cryoprotection in certain organisms. Antifreeze proteins are an evolutionary adaptation that contributes to the freeze resistance of certain fish, insects, bacteria and plants. These proteins adsorb to an ice crystal's surface and restrict its growth within a certain temperature range. We investigated the ability of an antifreeze protein from the desert beetle Anatolica polita, ApAFP752, to confer cryoprotection in the frog Xenopus laevis. Xenopus laevis eggs and embryos microinjected with ApAFP752 exhibited reduced damage and increased survival after a freeze-thaw cycle in a concentration-dependent manner. We also demonstrate that ApAFP752 localizes to the plasma membrane in eggs and embryonic blastomeres and is not toxic for early development. These studies show the potential of an insect antifreeze protein to confer cryoprotection in amphibian eggs and embryos.
Project description:Veronica polita Fr. 1819 (synonym: Veronica didyma Ten. 1981) is a species of annual herb with high medicinal value. It is originally from Southwest Asia, but has been naturalized widely in many regions of the world. In this study, the complete chloroplast genome of V. polita was determined to be 150,191 bp long with a typical quadripartite structure, comprising two inverted repeat regions (IRa and IRb, 25,465 bp each), a large single-copy (LSC) region (81,847 bp) and a small single-copy (SSC) region (17,414 bp). It encodes a panel of 114 genes (including 79 protein-coding, 31 tRNA, and four rRNA genes) with 18 of them being completely or partially duplicated and 19 of them possessing one or two introns. Phylogenetic analysis supported the tribal-level taxonomy of the family Plantaginaceae, and revealed that V. polita was most closely related to the congener Veronica persica Poir. 1808.
Project description:BackgroundThe temporal dynamics of insect populations in tropical environments is highly complex and poorly known. Long-term seasonality studies are scarce, and particularly so for ichneumonid wasps (Hymenoptera Ichneumonidae). This study represents an effort to elucidate aspects of seasonality and forest succession in the Brazilian Atlantic Forest.New informationWe report on the seasonal and successional dominance of the ichneumonid wasp Trihapsis polita (Cryptinae). A long-term survey of Cryptinae was carried out in a protected area of Brazilian Atlantic Forest, in primary, tall secondary and low secondary forest areas. Specimens were collected during rainy season (RS) and dry season (DS) between 2000 and 2008, with total sampling effort of 4,095 trap-days. A total of 8,385 specimens of Cryptinae were collected, of which 6,655 (79.4%) belonged to T. polita. The occurrence of T. polita species was heavily concentrated in the RS, with abundance 148× higher than during the DS. Seasonal fluctuation was also detected for Cryptinae as a whole, but was two orders of magnitude lower. Sampling efficiency also varied widely among areas, with the peak of abundance at the tall secondary forest. The dominance of T. polita in secondary vegetation might be of general interest, as this type of forest is currently on the rise, due to unprecedented levels of human pressure.