动植物基蛋白对高蛋白冰淇淋质构品质的影响

为了保证高蛋白冰淇淋可以达到目前普通蛋白含量冰淇淋的质构稳定性,该文研究了以脱脂奶粉、浓缩乳清蛋白、大豆分离蛋白制备的冰淇淋在普通蛋白含量(3%,质量分数)和高蛋白含量(5%,质量分数)下的质构表现,并在高蛋白含量下通过不同动植物基蛋白复配(脱脂奶粉与大豆分离蛋白、浓缩乳清蛋白与大豆分离蛋白),以克服高蛋白含量对质构性质的不利影响。研究表明,在高蛋白浓度下,脱脂奶粉与浓缩乳清蛋白冰淇淋整体抗融性下降,抗塌陷能力减弱;大豆分离蛋白冰淇淋融化速率提升,但起滴时间延长,抗塌陷能力较稳定。复配体系中大豆分离蛋白比例的增加,能使抗融性得到改善,获得相对较好且稳定的抗塌陷能力,但硬度和黏附力会显著上升。其中,浓缩乳清蛋白与大豆分离蛋白质量比为1∶1时,各质构性质较为平衡,可获得较优的高蛋白冰淇淋质构品质。

Virus Movement Protein Gene Mediated Resistance Against Cucumber Mosaic Virus Infection

Tobacco ( Nicotiana tabacum L.) “NC89” plants were transformed with deletion mutant of cucumber mosaic virus (CMV) movement protein (MP) gene and full_length CMV MP gene, respectively. The transformed plants were analyzed with polymerase chain reaction (PCR), PCR_Southern, Southern and Western blots. R 0 generation of the transgenic plants were inoculated with CMV. Five out of 10 lines of tobacco plants (BMPK) transformed with CMV MP deletion mutant gene showed high resistance to CMV infection and remained symptomless for up to 50 days post_inoculation. In contrast, tobacco plants (BMPR) transformed with full_length CMV MP gene did not show resistance to CMV infection. However, most of the infected full_length CMV MP gene transgenic plants recovered by showing none or very mild mosaic symptoms in 40 days post_inoculation. The results of R 1 generation of the BMPK transgenic plants tested under field conditions showed that all 5 lines of transgenic plants could delay the virus disease development.

A survey on porcine circovirus type 2 infection and phylogenetic analysis of its ORF2 gene in Hangzhou,Zhejiang Province,China

Porcine circovirus type 2 (PCV2) is closely related to the postweaning multisystemic wasting syndrome (PMWS). In this study, the pig serum and tissue samples collected from different regions of Hangzhou District in Zhejiang Province of China between 2003 and 2005 were analyzed by enzyme-linked immunosorbent assay (ELISA) for PCV2 antibody and by polymerase chain reaction (PCR) for ORF2 gene. The results show that out of 1250 randomly collected serum samples, 500 sera (40%) were seropositive for PCV2. PCR results demonstrate that Hangzhou PCV2 with more than 50% Chinese PCV2 strains and French PCV2 formed Cluster A. Only one PCV2 from Hangzhou belonged to Cluster B with some other Chinese PCV2 and Netherlands’s isolates. Cluster C consisted of PCV2 isolates from China, US, Canada, UK and Germany. The results indicate that the PCV2 infection was widespread in Hangzhou.

Adenovirus-mediated CTLA4Ig gene inhibits infiltration of immune cells and cell apoptosis in rats after liver transplantation

AIM: To investigate the role of adenovirus-mediated CTLA4Ig gene therapy in inhibiting the infiltration of macrophages and CD8+T cells and cell apoptosis after liver transplantation. METHODS: The rat orthotopic liver transplantation model was applied. The rats were divided into three groups: group I: rejection control (SD-to-Wistar); group II: acute rejection treated with intramuscular injection of CsA 3.0 mg/(kg·d) for 12 d (SD-to-Wistar+CsA); groupIII: injection of 1×109 PFU adenovirus-mediated CTLA4Ig gene liquor in dorsal vein of penis 7 d before liver transplantation (SD-to-Wistar+CTLA4Ig). Immunohistochemistry and transferase-mediated dUTP nick-end labeling (TUNEL) were used to analyze the expression of CTLA4Ig gene in liver, infiltration of macrophages and CD8+T cells, cell apoptosis in grafts at different time-points after liver transplantation. Histopathological examination was done. RESULTS: CTLA4Ig gene expression was positive in liver on d 7 after administering adenovirus-mediated CTLA4Ig gene via vein, and remained positive until day 60 after liver transplantation. Infiltration of macrophages and CD8+T cells in CTLA4Ig-treated group was less than in rejection control group and CsA-treated group. The apoptotic index of rejection group on d 3, 5, and 7 were significantly higher than that of CTLA4Ig-treated group. A good correlation was found between severity of rejection reaction and infiltration of immune activator cells or cell apoptotic index in grafts. CONCLUSION: CTLA4Ig gene is constantly expressed in liver and plays an important role in inducing immune tolerance.

Cumulus-specific genes are transcriptionally silent following somatic cell nuclear transfer in a mouse model

This study investigated whether four cumulus-specific genes: follicular stimulating hormone receptor (FSHr), hyaluronan synthase 2 (Has2), prostaglandin synthase 2 (Ptgs2) and steroidogenic acute regulator protein (Star), were correctly reprogrammed to be transcriptionally silent following somatic cell nuclear transfer (SCNT) in a murine model. Cumulus cells of C57×CBA F1 female mouse were injected into enucleated oocytes, followed by activation in 10 μmol/L strontium chloride for 5 h and subsequent in vitro culture up to the blastocyst stage. Expression of cumulus-specific genes in SCNT-derived embryos at 2-cell, 4-cell and day 4.5 blastocyst stages was compared with corresponding in vivo fertilized embryos by real-time PCR. It was demonstrated that immediately after the first cell cycle, SCNT-derived 2-cell stage embryos did not express all four cumulus-specific genes, which continually remained silent at the 4-cell and blastocyst stages. It is therefore concluded that all four cumulus-specific genes were correctly reprogrammed to be silent following nuclear transfer with cumulus donor cells in the mouse model. This would imply that the poor preimplantation developmental competence of SCNT embryos derived from cumulus cells is due to incomplete reprogramming of other embryonic genes, rather than cumulus-specific genes.

Phylogenetic studies of four species of ciliate inferred from 16s-like small subunit rRNA gene sequences

The phylogenetic relationships of four ciliate genera （Urostyla, Euplotes, Stylonychia and Pseudokeronopsis）, which also are the important environment inspection species, were analyzed by the comparison of small subunit ribosomal RNA gene sequences. Euplotes appeared as an early branching group whose divergence from the hypotrichous line at a deep level was strongly supported by parsimony and matrix analyses. The analyses also supported the hypothesis that there were closely relationship between species in Urostyla and Holosticha. The sibling species Stylonychia mytilus and S. lemnae could be separated by the evolutionary analyses. Furthermore, Pseudokeronopsis rubra had relatively more closely relationship with the species in Holostichidae than that in Urostylidae based on the evolutionary distance value.

Gene Flow from Transgenic Chinese Cabbage (Brassica campestris ssp. chinensis var.utilis) to Related Cruciferae Species Through Outcrossing

It was substantiated by morphological observation, chromosome and DNA identification that the bar gene, conferring the resistance to herbicide basta in transgenic Chinese cabbage ( Brassica campestris ssp. chinensis var. utilis Tsen et Lee), could intrude into the genomes of turnip ( B. campestris ssp. rapifera), heading Chinese cabbage B. campestris ssp. pekinensis) and other non-heading Chinese cabbage ( B. campestris ssp. chinensis in a relatively high frequency while into genome of B. napus at a low frequency via natural cross-pollination in open field. Herbicide resistant hybrids of B. nigra, B. carinata, and B. juncea could be obtained at certain frequency in the greenhouse by hand pollination. At no time did the resistant hybrid plants of transgenic Chinese cabbage with B. oleracea, R. sativus and seven wild weeds, widespread in China, gained in our experiments.

Transformation of Poplar (Populus)with tPA Gene

In this study, tPA gene(human tissuetype plasminogen activator gene) was remolded with the leader sequence removed and an artificially synthesized sequence containing the initiator (ATG) added. Using the binary vector strategy,we first inserted the remolded tPA gene into the Ti-derived plasmid, PGA643 and then transferred,in a triparental mating system,the plasmid into a strain of Agrobacterium tumefaciens,A281, that contained vir-DNA.Finally poplar cells were transformed with A. tumefaciens using leaf discus method. The transformed cells were selected in culture containing kanamycin and in siyu hybridization.Successful generation of transgenic poplar was demonstrated by molecular hybridization in the cultivated plants and detection of tPA gene product.

A comparative study of distant hybridization in plants and animals

Distant hybridization refers to crosses between two different species, genera, or higher-ranking taxa, which can break species limits, increase genetic variation, and combine the biological characteristics of existing species. It is an important way of creating genetic variation, fertile strains, and excellent characteristics in new strains and populations. Combining analyses and summaries from many inter-related documents in plants and animals, both domestic and international, including examples and long-standing research on distant hybridization in fish from our laboratory, we summarize and compare the similarities and differences in plant and animal distant hybridization. In addition, we analyze and review the biological characteristics of their different ploidy progenies and the possible causes of disparity in survival rates. Mechanisms of sterility in animal and plant distant hybrids are also discussed, and research methods for the study of biological characteristics of hybrids, including morphology, cytology,and molecular cytogenetics are presented. This paper aims to provide comprehensive research materials and to systematically compare the general and specific characteristics of plant and animal hybrids with regards to reproduction, genetics, growth traits,and other biological characteristics. It is hoped that this paper will have great theoretical and practical significance for the study of genetic breeding and biological evolution of plant and animal distant hybridization.

H_2S synthetase At D-CDes involves in ethylene and drought regulated stomatal movement

The endogenous hydrogen sulfide （H2S）, as a new gasotransmitter, participates in many plant physio- logical processes. In this study, we found that both ethylene and drought strongly induced HaS synthetase AtD-CDes gene expression and enzymatic activity. H2S synthesis inhibitors restrained the ethylene and drought induced stomatal closure in Arabidopsis. The H2S synthetase mutant Atd-cdes was insensitive to ethylene and drought, and overexpression of AtD-CDes conferred the transgenic plants more sensitive to ethylene and drought. Sequence analysis of AtD-CDes promoter showed that it contained ethylene response cis element ERE, and abiotic stress responsive cis elements MBS, LTR, and ABRE. The AtD- CDes promoter fused with GUS was transformed into Arabidopsis thaliana to get AtD-CDes promoter：：GUS transgenic plants. When treated with ethylene and drought stress, the enzymatic activity of fl-glucuronidase was higher in the leaves and stomata of transgenic Arabidopsis. Analyses of GUS activity from the transgenic plants har- boring different fragments of the promoter shows that the key section of AtD-CDes promoter response to ethylene was from the -697 to -408 bp, and the key section response to drought stress was from -90 to -1 bp. These results suggested that the H2S produced from AtD-CDesmay mediate ethylene and drought-induced stomatal movement.