ANALYSIS OF Lyl1 EXPRESSION AS A FREQUENT PARTNER OF LMO2 IN T-CELL LEUKEMOGENESIS IN HUMAN

Objective： To identify aberrant gene expression in primary human T-cell acute lymphoblastic leukemia （T-ALL） and to evaluate the differently expressed level of Lyll and LMO2 genes in human LMO2 positive/TALl negative T-ALL tumors. Methods： Three methods, representational difference analysis （RDA） of cDNA, cDNA microarrays and RT-PCR were used to detect if Lyll and LMO2 genes were differently expressed in human LMO2 positive/tall negative T-ALL tumors. Results： The results of cDNA RDA and cDNA array shown that Lyll and LMO2 genes are differently expressed in human T-cell tumors. The result of RT-PCR also shown Lyll and LMO2 are high expressed in human T-cell tumors and very low level or no expressed in normal group. Conclusion： We have found that cDNA RDA and cDNA microarray can be successfully used to identify aberrant gene expression in T-ALL cells. In the study described in this manuscript we found that Lyll and LMO2 are aberrantly expressed in human T-ALL LMO2 positive/TALl negative T-ALL tumors.

拉林河浮游植物三种功能群分布特征及其与环境因子的关系

浮游植物是河流生态系统能量流动与信息传递的关键环节。浮游植物及其功能性状对于水体水文条件、理化特征及气候变化敏感,因此被广泛应用于水体环境监测。拉林河流域是我国北方重要稻米基地和商品粮基地,受农业面源污染严重。然而,拉林河流域浮游植物群落演替规律尚不明确,基于不同生态属性的功能群对拉林河环境的指示意义仍不清晰。于2021年春季和夏季在拉林河流域设置23个采样点对浮游植物群落进行定性定量分析。基于浮游植物功能群(functional group,FG)、生态功能群(morpho-functional group,MFG)和形态功能群(morphology-based functional group,MBFG)分析浮游植物群落演替特征。通过冗余分析(redundancy analysis,RDA)揭示驱动浮游植物群落演替的关键环境因子。结果显示,研究期间拉林河流域浮游植物群落演替明显,划分FG功能群25个,MFG功能群24个,MBFG功能群7个。FG、MFG和MBFG功能群的演替受多种环境因素共同影响,其中水温(water temperature,WT)和总氮(total nitrogen,TN)与功能群演替关系密切。经研究表明FG功能群能更好的响应拉林河流域水环境的时空异质性。相较于传统的林奈分类法,FG功能群提供了高效、简便且能反映生态信息的划分方式。在未来对于拉林河流域水生生物多样性保护及环境监测研究中,FG功能群是可靠的研究手段。

阿什河流域底栖硅藻群落特征及水环境健康评价

为探索黑龙江省阿什河流域底栖硅藻群落特征及环境相关性,并对阿什河流域进行水环境健康评价,本研究于2018年7月(丰水期)和2018年10月(枯水期)对阿什河流域8个典型采样点进行调查。基于相似性分析检验(analysisofsimilarities,ANOSIM)和相似百分比分析(similarity percentages,SIMPER)分析探索枯水期与丰水期之间底栖硅藻的群落差异,通过冗余分析(redundancyanalysis,RDA)对驱动底栖硅藻的关键环境因子进行筛选;使用硅藻生物指数(biological diatom index,IBD)、硅藻属指数(generic index of diatom,GI)和水体营养指数(trophic state index,TSI)对研究区域水体营养状态进行初步评价。结果表明,研究期间共鉴定底栖硅藻89种,其中丰水期80种、枯水期57种。独立样本T检验(T-test)表明阿什河流域物种丰富度丰水期显著高于枯水期(P<0.05),Shannon-wiener指数变化不显著(P>0.05)。ANOSIM结合SIMPER分析结果显示阿什河流域硅藻群落格局存在一定的时空异质性。RDA分析表明水的电导率是驱动阿什河流域底栖硅藻空间分布的环境因子,枯水期与丰水期之间高锰酸盐指数(CODMn)含量的变化是影响硅藻群落演替的因素之一。IBD、GI和TSI指数结果显示阿什河流域受人为活动干扰区域营养状态较差,IBD指数较GI指数能更有效的反映阿什河流域水体营养状况。

Soil Microbial Community Composition During Natural Recovery in the Loess Plateau, China

This study aimed to determine the characteristics of soil microbial community composition and its relationship with soil chemical properties during natural recovery in the Loess Plateau.The soil microbial community composition was analyzed by comparing the soil microbial phospholipid fatty acids（PLFAs） of eight croplands abandoned for 1,3,5,10,13,15,20,and 30 yr in the Dunshan watershed,northern Loess Plateau,China.The results showed that soil organic carbon,total nitrogen,soil microbial biomass carbon,and soil microbial biomass nitrogen significantly increased with the abandonment duration,whereas the metabolic quotient significantly decreased.The Shannon richness and Shannon evenness of PLFAs significantly increased after 10 yr of abandonment.Gram-negative,Gram-positive,bacterial,fungal,and total PLFAs linearly increased with increased abandonment duration.Redundancy analysis showed that the abandonment duration was the most important environmental factor in determining the PLFA microbial community composition.The soil microbial PLFAs changed from anteiso-to iso-,unsaturated to saturated,and short-to long-chain during natural recovery.Therefore,in the Loess Plateau,cropland abandonment for natural recovery resulted in the increase of the soil microbial PLFA biomass and microbial PLFA species and changed the microbial from chemolithotrophic to a more heterotrophic community.

Precipitation and soil particle size co-determine spatial distribution of biological soil crusts in the Gurbantunggut Desert, China

Biological soil crusts （BSCs） are bio-sedimentary associations that play crucial ecological roles in arid and semi-arid regions. In the Gurbantunggut Desert of China, more than 27% of the land surface is characterized by a predominant cover of lichen-dominated BSCs that contribute to the stability of the desert. However, little is known about the major factors that limit the spatial distribution of BSCs at a macro scale. In this study, the cover of BSCs was investigated along a precipitation gradient from the margins to the center of the Gurbantunggut Desert. Environmental variables including precipitation, soil particle size, soil pH, electrical conductivity, soil organic carbon, total salt, total nitrogen, total phosphorus and total potassium were analyzed at a macro scale to determine their association with differing assemblages of BSCs （cyanobacteria crusts, lichen crusts and moss crusts） using constrained linear ordination redundancy analysis （RDA）. A model of BSCs distribution correlated with environmental variables that dominated the first two axes of the RDA was constructed to clearly demonstrate the succession stages of BSCs. The study determined that soil particle size （represented by coarse sand content） and precipitation are the most significant drivers influencing the spatial distribution of BSCs at a macro scale in the Gurbantunggut Desert. The cover of lichen and moss crusts increased with increasing precipitation, while the cover of cyanobacteria crusts decreased with increasing precipitation. The cover of lichen and moss crusts was negatively associated with coarse sand content, whereas the cover of cyanobacteria crusts was positively correlated with coarse sand content. These findings highlight the need for both the availability of soil moisture and a relatively stable of soil matrix, not only for the growth of BSCs but more importantly, for the regeneration and rehabilitation of disturbed BSC communities in arid and semi-arid lands. Thereby, this study will provide a theory basis to effectively increase soil stability in desert regions.

Fish-mediated changes in bacterioplankton community composition: an in situ mesocosm experiment

We characterized variations in bacterioplankton community composition(BCC) in mesocosms subject to three different treatments. Two groups contained fish(group one: Cyprinus carpio; group two: Hypophthalmichthys molitrix); and group three, the untreated mesocosm, was the control. Samples were taken seven times over a 49-d period, and BCC was analyzed by PCR-denaturing gradient gel electrophoresis(DGGE) and real-time quantitative PCR(q PCR). Results revealed that introduction of C. carpio and H. molitrix had a remarkable impact on the composition of bacterioplankton communities, and the BCC was significantly diff erent between each treatment. Sequencing of DGGE bands revealed that the bacterioplankton community in the different treatment groups was consistent at a taxonomic level, but differed in its abundance. H. molitrix promoted the richness of Alphaproteobacteria and Actinobacteria, while more bands affiliated to Cyanobacteria were detected in C. carpio mesocosms. The redundancy analysis(RDA) result demonstrated that the BCC was closely related to the bottom-up(total phosphorus, chlorophyll a, phytoplankton biomass) and top-down forces(biomass of copepods and cladocera) in C. carpio and control mesocosms, respectively. We found no evidence for top-down regulation of BCC by zooplankton in H. molitrix mesocosms, while grazing by protozoa(heterotrophic nanoflagellates, ciliates) became the major way to regulate BCC. Total bacterioplankton abundances were significantly higher in C. carpio mesocosms because of high nutrient concentration and suspended solids. Our study provided insights into the relationship between fish and bacterioplankton at species level, leading to a deep understanding of the function of the microbial loop and the aquatic ecosystem.

Methanogenic community dynamics in anaerobic co-digestion of fruit and vegetable waste and food waste

A lab-scale continuously-stirred tank reactor （CSTR）, used for anaerobic co-digestion of fruit and vegetable waste （FVW） and food waste （FW） at different mixture ratios, was operated for 178 days at the organic loading rate of 3 kg VS （volatile solids）/（m3.day）. The dynamics of the Archaeal community and the correlations between environmental variables and methanogenic community structure were analyzed by polymerase chain reactions - denaturing gradient gel electrophoresis （PCR-DGGE） and redundancy analysis （RDA）, respectively. PCR-DGGE results demonstrated that the mixture ratio of FVW to FW altered the community composition of Archaea. As the FVW]FW ratio increased, Methanoculleus, Methanosaeta and Methanosarcina became the predominant methanogens in the community. Redundancy analysis results indicated that the shift of the methanogenic community was significantly correlated with the composition of acidogenic products and methane production yield. Different mixture ratios of substrates led to different compositions of intermediate metabolites, which may affect the methanogenic community. These results suggested that the analysis of microbial communities could be used to diagnose anaerobic processes.