RAPD analysis of natural populations of Acanthopanax brachypus

Random Amplified Polymorphic DNA (RAPD) analysis is a new technology of molecular marking which has proved very powerful in detecting genetic diversity at the level of population. The genomic DNAs used in our experiment were extracted from fresh leaves taken from 59 individuals sampled from three natural populations in Yan An, Shanxi Province. Through more than 2,000 PCRs, deep-going RAPD analysis was carried out on DNA samples from 49 inviduals. The percentage of polymorphic RAPD loci found in these three populations were respectively 27.2 %, 18.6 % and 5.4 %; the average genetic distances within population, 0.055, 0.036 and 0.008; the average genetic distances between populations (Ⅰ-Ⅱ), (Ⅰ-Ⅲ) and (Ⅱ-Ⅲ), 0.105, 0.096 and 0.060. The genetic diversity of A. brachypus within and between populations was found, for the first time, to be rather poor,thus revealing innate factors as the cause contributing to its endangered status. In addition, our work also provides basic materials for elucidating the underlying cause of its endangerment and for its protection biology.

Incorporation of Resistance Gene into Tomato using Binary Vector System

Exoplants of tomato(Lycopersicon esculentum) leaf were transformed with Ti plasmids using binary vector system.After screening.with selection culture, kanamycin-resistant seedling were obtained from callus. Molecular hybridization proved the integration of Km gene into plant cell genome via A.tumefaciens. Higher activity of Nos-NPTase was demonstrated in the transformed plant,thus confirming the successful expression of the resistance gene in recipient cells.

The Study of Enzymology Characterization of Ctenopharyngodon idellus LDH Isozyme

LDH-A_4,B_4,and C_4 were isolated and purified from Ctenopharyngodon idellus tissues by means ofaffinity chromatography.The purity,amino acid content and kinetics were analyzed.The anti-LDH-A_4,B_4,and C_4 antibodies were prepared from rabbit sensitized by LDH-A_4,B_4,and C_4respectively.The LDH patterns of some freshwater fish and marine fish were identified by theantigen-antibody precipitation reaction.The homology between LDH isozyme molecules fromdifferent sources and the immunological homology of different LDH isozymes were discussed.

Detection and Analysis of an Estrous－associated Oviductal Glycoprotein DNA Fragment from Primates by PCR

DNA was extracted from lymphocytes of primates and PCR was used to amplify the estrous-associated glycoprotein DNA fragment. 537 kb DNA fragments from crab eating macaque were detected. Sequences from chimpanzee, orangutan and human were also amplified, but they were shorter than predicted. We were unable to amplify sequences from spider monkey, salmon, several rodents, bandicoot, sheep and pig . Analysis of the restriction map revealed several conserved RE sites in the amplified sequences of the primates. The results support the view that monkey has more close relationship with human than any other species at molecular level.

Cloning and Sequencing of the cDNA Fragment Containing Sorghum Actin Gene（SoAcl）

A cDNA library containing 2×10￣6 recombinant plasmids was constructed using one week old young sorghum leaves as starting material and λgt10 as vector. In in situ hybridization, 2 positive clones were selected using as probe RAcl cDNA from rice . One of them was subjected to Southern blot analysis and the recombinant containing the cDNA of SoAcl thus found was subcloned into pBluescript SK for sequencing. As shown by sequencing,SoAcl is composed of 1445 bps and 377 amino acids are encoded by the 1131 bp encoding region. It is the first report on it and has been included in the EMBO BANK (regist. no. X79378). High homology is found between it and other plant actin genes so far reported. The homology of amino acids sequency with RAcl is as high as 97.5%. Besides, highly homologous structural domains are found when it is compared with other plant and animal actins. These structural domains, thought to he sites for interaction among actins and/or between actins and their binding proteins, may prove to be important in the functioning of actin.(1 PhD candidate in Beijing University 2 Visiting Research Fellow of College of Oral Medicine of Beijing Medical University 3 Research Fellow of Institute of Developmental Biology, to whom correspondence is addressed 3 Reseach Fellow of Institute of Developmental Biology,to whom correspondence is addressed)

Structural Analysis of rbcL Gene from an Endangered Plant，（Acanthopanax brachypus）

A 3.2 kb EcoRI DNA fragment containing the complete chloroplast rbcL gene from Acanthopanax brachypus has been cloned. In addition to the 1428 bp coding region encoding 475 amino acids of the gene, 278 bp upstream and 218 bp downstream were also sequenced. Possible ctpl and ctp2, equivalent to prokaryotic-35 and -10 elements, were found as TTGCGC and TACAAT respectively. The 5' untranslated leader region is 194 bp and the putative ribosome binding site in this region is GGAGG,located immediately upstream of the start codon. The 3' unrtanslated region contains two inverted repeat sequences, which in the mRNA might form stem-loop structures. The homology of rbcL amino acid sequence between A. brachypus and tobacco, spinach, pea, alfalfa, maize, rice, pine,Marchantia, Chlamydomonas and Anacystis are, respectively 93.05%,94.11%, 94.53%,89.68%, 92.21%, 2.21%, 92.63%, 87.58% and 80.84%.The promoter regions and part of the 5', 3' non-coding regions of rbcL from various plants were compared.