Two related,low-temperature-induced genes from Brassica napus are homologous to the human tumour bbc1 (breast basic conserved) gene

In order to identify genes involved in cold acclimation, we have constructed a cDNA library from Brassica napus (cv. Samouraï) cold-acclimated etiolated seedlings. By differential screening, a cDNA clone named pBnC24 (Brassica napus Cold), corresponding to a new cold-inducible plant gene, was isolated. Northern blot hybridizations using total RNA from acclimated and unacclimated seedlings confirmed that BnC24 represents a cold-regulated gene. In contrast with a number of cold-inducible plant genes, BnC24 does not seem to be responsive to abscisic acid (ABA). In addition, further screening of the cold-acclimated cDNA library using pBnC24 cDNA as a probe, allowed the isolation of a second type of homologous cDNA. Sequence analysis showed that the two BnC24 genes encode basic 24 kDa proteins, which are highly hydrophilic and rich in alanine, lysine and arginine. The nucleotide and deduced amino acid sequences of these clones do not show any homology with other previously described cold-induced plants genes. However they have strong homology with a recently discovered human tumour gene, bbc1 (breast basic conserved), which seems to be highly conserved in eukaryotes.     

DNA repair mechanisms in dividing and non-dividing cells

DNA damage created by endogenous or exogenous genotoxic agents can exist in multiple forms, and if allowed to persist, can promote genome instability and directly lead to various human diseases, particularly cancer, neurological abnormalities, immunodeficiency and premature aging. To avoid such deleterious outcomes, cells have evolved an array of DNA repair pathways, which carry out what is typically a multiple-step process to resolve specific DNA lesions and maintain genome integrity. To fully appreciate the biological contributions of the different DNA repair systems, one must keep in mind the cellular context within which they operate. For example, the human body is composed of non-dividing and dividing cell types, including, in the brain, neurons and glial cells. We describe herein the molecular mechanisms of the different DNA repair pathways, and review their roles in non-dividing and dividing cells, with an eye toward how these pathways may regulate the development of neurological disease.     

Cloning and characterization of a cDNA encoding human differentiation antigen 5D4

A 1 846 bp cDNA is isolated from a human tonsil cell λgt 11 cDNA library (ATCC No. 37546) with mAb 5D4 reactive strongly with human B cell line 3D5, but weakly with human B cell line Daudi and human T cell line Jurkat as a probe. RT-PCR also shows a strong reaction in 3D5 cell and a weak reaction in Daudi and Jurkat cell for 5D4 mRNA. There is an open reading frame from 88 to 1 209 bp in 5D4 cDNA encoding a 374 AA protein. Both the Northern blot analysis and the two consecutive stop codens before start coden demonstrate that the cDNA is a full-length cDNA. Secondary structure prediction suggests that there are a region from 295 to 334 AA in the protein with strong hydrophobicity and a transmembrane helix region with high score from 313 to 334 AA with an orientation from the inside to the outside of the cell.     

Fibrotic enzymes modulate wound‐induced skin tumorigenesis

Fibroblasts are a major component of the microenvironment of most solid tumours. Recent research elucidated a large heterogeneity and plasticity of activated fibroblasts, indicating that their role in cancer initiation, growth and metastasis is complex and context‐dependent. Here, we performed genome‐wide expression analysis comparing fibroblasts in normal, inflammatory and tumour‐associated skin. Cancer‐associated fibroblasts (CAFs) exhibit a fibrotic gene signature in wound‐induced tumours, demonstrating persistent extracellular matrix (ECM) remodelling within these tumours. A top upregulated gene in mouse CAFs encodes for PRSS35, a protease capable of collagen remodelling. In human skin, we observed PRSS35 expression uniquely in the stroma of high‐grade squamous cell carcinomas. Ablation of PRSS35 in mouse models of wound‐ or chemically‐induced tumorigenesis resulted in aberrant collagen composition in the ECM and increased tumour incidence. Our results indicate that fibrotic enzymes expressed by CAFs can regulate squamous tumour initiation by remodelling the ECM.     

Targeting of T7 RNA polymerase to tobacco nuclei mediated by an SV40 nuclear location signal

We have expressed two T7 RNA polymerase genes by electroporation into tobacco protoplasts. One of the genes was modified by inserting nucleotides encoding a viral nuclear localization signal (NLS) from the large T antigen of SV40. Both T7 RNA polymerase genes directed synthesis of a ca. 100 kDa protein in the electroporated protoplasts. T7 RNA polymerase activity was detected in extracts of protoplasts electroporated with both genes. Immunofluorescence analysis of these protoplasts indicated that only the polymerase carrying the NLS accumulated in the cell nucleus. These experiments suggest that mechanisms involved in the transport from the cytoplasm to the nucleus are similar in plant and animal cells. This system demonstrates the feasibility of T7 RNA polymerase-based approaches for the high-level expression of introduced genes in plant cells.     

Kidney proteome responses in the teleost fish Paralichthys olivaceus indicate a putative immune response against Streptococcus parauberis

The proteomic response to bacterial infection in a teleost fish (Paralichthys olivaceus) infected with Streptococcus parauberis was analyzed using label-free protein quantitation coupled with LC-MS(E) tandem mass spectrometry. A total of 82 proteins from whole kidney, a major lymphoid organ in this fish, were found to be differentially expressed between healthy and diseased fish analyzed 6, 24, 72 and 120 h post-infection. Among the differentially expressed proteins, those involved in mediating immune responses (e.g., heat shock proteins, cathepsins, goose-type lysozyme and complement components) were most significantly up-regulated by infection. In addition, cell division cycle 48 (CDC48) and calreticulin, which are associated with cellular recovery and glycoprotein synthesis, were up-regulated in the universal protein group, whereas the other proteins in that group were down-regulated. There was continuous activation of expression of immune-associated proteins during infection, but there was also loss of expression of proteins not involved in immune function. We expect that our findings regarding immune response at the protein level would offer new insight into the systemic response to bacterial infection of a major immune organ in teleost fish.     

生物多样性相关传统知识调查与评估: 以澜沧与康定两县域为例

本研究依据《县域生物多样性相关传统知识调查与评估技术规定》, 调查评估了云南省澜沧县和四川省康定市两县域生物多样性相关传统知识的分布数量与特征, 分析了传统知识保护与传承状况, 识别了主要受威胁因素和保护空缺, 旨在为我国传统知识保护和民族地区实施传统知识获取与惠益分享制度提供科学依据, 推动《生物多样性公约》与《名古屋议定书》等国际公约的履行。研究结果如下: 分别调查编目澜沧县、康定市的生物多样性相关传统知识145项、98项; 这些传统知识具有明显的地区气候与自然环境特征、生产生活实践特征、传统文化特征和地区社会经济特征; 相关部门在传统知识保护管理方面做出了积极努力, 同时包括习惯法、传统节庆等传统文化和包括祭祀、神山、神林等宗教方式在内的地方社区行动在传统知识保护与传承方面也发挥了重要作用; 生物多样性相关传统知识、创新和做法已被广泛应用于地方社区脱贫攻坚和产业发展; 传统知识保护立法仍不健全、受到威胁、保护意识薄弱及承载传统知识的生物资源减少是制约传统知识保护传承的主要因素。两县域生物多样性相关传统知识丰富, 并且地方社区有效参与了生物多样性相关传统知识的保护与可持续利用。今后应建立传统知识获取与惠益分享国家制度; 加强宣传教育, 提升保护传承意识; 因地制宜开展传统知识保护; 推动传统知识相关生物资源的保护与可持续利用。     

Purification and biochemical characterization of two novel antigens from Leishmania major promastigotes

The identification and characterization of antigens that elicit human T cell responses is an important step toward understanding of Leishmania major infection and ultimately in the development of a vaccine. Micropreparative SDS-PAGE followed by electrotransfer to a PVDF membrane and elution of proteins from the PVDF, was used to separate 2 novel proteins from L. major promastigotes, which can induce antibodies of the IgG2a isotype in mice and also are recognized by antisera of recovered human cutaneous leishmaniasis subjects. Fractionation of the crude extract of L. major revealed that all detectable proteins of interest were present within the soluble Leishmania antigens (SLA). Quantitation of these proteins showed that their expression in promastigotes is relatively very low. Considering the molecular weight, immunoreactivity, chromatographic and electrophoretic behavior in reducing and non-reducing conditions, these proteins are probably 2 isoforms of a single protein. A digest of these proteins was resolved on Tricine-SDS-PAGE and immunoreactive fragments were identified by human sera. Two immunoreactive fragments (36.4 and 34.8 kDa) were only generated by endoproteinase Glu-C treatment. These immunoreactive fragments or their parent molecules may be ideal candidates for incorporation in a cocktail vaccine against cutaneous leishmaniasis.     

~(125)Ⅰ标记单抗LC-I与肺腺癌细胞体内外结合特性的研究

本文用~(125)Ⅰ标记LC-1进行了一些体内外实验。实验结果表明:LC-1单抗的结合常数为4.8×10~8M~(-1),LC-1针对的SPC-A_1细胞表面抗原的位点数为7.2×10~4/细胞;LC-1与LAC-122两单抗针对的抗原决定簇没有交叉;用蛋白酶和过碘酸钠处理SPC-A_1细胞,前者对LC-1的结合抑制39%,后者抑制66%;LC- 1不但有较强的体外结合靶细胞的能力,从LC-1在荷瘤裸鼠中的组织器官分布来看,LC-1与肿瘤有较高的体内亲和性,并且是特异性的结合。