Lamprey VDAC2: Suppressing hydrogen peroxide-induced 293T cell apoptosis by downregulating BAK expression.

The voltage-dependent anion channel 2 (VDAC2) is the abundant protein in the outer mitochondrial membrane. Opening VDAC2 pores leads to the induction of mitochondrial energy and material transport, facilitating interaction with various mitochondrial proteins implicated in essential processes such as cell apoptosis and proliferation. To investigate the VDAC2 in lower vertebrates, we identified Lr-VDAC2, a homologue of VDAC2 found in lamprey (Lethenteron reissneri), sharing a sequence identity of greater than 50 % with its counterparts. Phylogenetic analysis revealed that the position of Lr-VDAC2 aligns with the lamprey phylogeny, indicating its evolutionary relationship within the species. The Lr-VDAC2 protein was primarily located in the mitochondria of lamprey cells. The expression of the Lr-VDAC2 protein was elevated in high energy-demanding tissues, such as the gills, muscles, and myocardial tissue in normal lampreys. Lr-VDAC2 suppressed H2O2 (hydrogen peroxide)-induced 293 T cell apoptosis by reducing the expression levels of Caspase 3, Caspase 9, and Cyt C (cytochrome c). Further research into the mechanism indicated that the Lr-VDAC2 protein inhibited the pro-apoptotic activity of BAK (Bcl-2 antagonist/killer) protein by downregulating its expression at the protein translational level, thus exerting an anti-apoptotic function similar to the role of VDAC2 in humans.

Lamprey prohibitin 2 inhibits non-small cell lung carcinoma cell proliferation by down-regulating the expression and phosphorylation levels of cell cycle-associated proteins.

Prohibitin 2 (PHB2) is an evolutionarily conserved and functionally diverse protein that plays an important role in multiple cellular functions, including cell proliferation, cell migration, and apoptosis, and is also known to participate in the process of tumorigenesis and development. In this study, the lamprey PHB2 (Lm-PHB2) gene was over-expressed in KRAS (kirsten rat sarcoma viral oncogene homolog)-mutated non-small cell lung carcinoma (NSCLC) cells to investigate its effect on cell proliferation. The effects of Lm-PHB2 protein on the proliferation of NSCLC cells were determined by treating cells with the purified recombinant Lm-PHB2 protein (rLm-PHB2) followed by cell counting kit (CCK) assays and flow cytometry. Analysis showed that rLm-PHB2 blocked cells in the G2 phase and inhibited the cell proliferation of A549, Calu-1, and NCI-H226 to various degrees. The effect on Calu-1 cells was the most obvious and was concentration- and time-dependent. Similarly, cells transfected with the pEGFP-N1-Lm-PHB2 plasmid also resulted in the suppression of proliferation in A549 cells and Calu-1 cells. Quantitative real-time polymerase chain reaction (qRT-PCR) showed that Lm-PHB2 inhibited cell proliferation by repressing the transcription of PLK1 (polo-like kinase 1), Wee1 (wee1 kinase), CCNB1 (cyclin B1), and CDC25C (cell division control protein 25C). According to western blot analysis, Lm-PHB2 not only down-regulated the expression of PLK1, Wee1, CCNB1, and CDC25C but also reduced the phosphorylation levels of CCNB1 and CDC25C, thus blocking Calu-1 cells in G2/M phase. Our findings demonstrate a function of lamprey PHB2 that may inhibit the proliferation of some NSCLC cells by down-regulating the expression and phosphorylation of cell cycle-associated proteins.

[Research on land use structure optimization based on nonpoint source dissolved nitrogen load estimation in Shuaishui watershed].

Regional Nutrient Management (ReNuMa) was applied to estimate dissolved nitrogen (DN) load and perform source apportionment in Shuaishui watershed during 2000-2010. Satisfactory performance of ReNuMa was revealed by the E(ns) and R2 of greater than 0.9 in calibrating and validating streamflow and DN. The average nonpoint DN load in this watershed was 1.11 x 10(3) t x a(-1), with the load intensity of (0.75 +/- 0.22) t x km(-2). Among all the land uses, paddy field had the largest DN load intensity [28.60 kg x (hm2 x a)(-1)], while forest had the least [2.71 kg x (hm2 x a)(-1)]. Agricultural land (including paddy, grain, cash crop, tea plant and orchard) contributed most to DN load in Shuaishui watershed, indicating that the human dominated agricultural activities was the major contributor of nonpoint source pollution. Land use structure optimization for Shuaishui watershed in 2015 was conducted under the rule of reducing pollutants loads and maximizing the agricultural output value. The results demonstrated that agricultural monetary growth was accompanied with the increasing DN load at the optimal level, although output increment was higher than that of DN load.