Bioscience

Progress in Latent Infection Maintenance Mechanism of KSNV

Kaposi’s sarcoma is a most commonly seen malignant tumor in AIDS infected patients, because of its pathogen, Kaposi’s sarcoma-associated herpesvirus (KSHV) remains latent in the host cells after infection and can not be eliminated from the body. The infection rate of KSHV in general population is about 5%. The latent infection maintenance mechanism of KSHV is a hot issue in this research field. In November 2009, the Journal of virology published on web the latest result of research obtained by Lan Ke Research Group of the Institut Pasteur of Shanghai, CAS in the latent infection maintenance mechanism of KSHV. The researchers found the interaction between cellular co-repressor TLE2 and cycle regulation switch cell RTA by using yeast two hybrid screening. TLE2 can respond to the change of RTA level in cells and effectively control the gene expression level and release of virion in the rise phase of KSHV by inhibiting the transcription activation through binding with RTA. Further research showed that TLE2 can replace transcription-activator bound with RTA and collect transcription initiation complex, so as to inhibit the transcription activation of RTA. This research reported TLE2 as a new RTA binding protein, revealed that the host cell plays an important role in the maintenance of latent infection of KSHV, further illustrated the latent infection mechanism of KSHV and offered a clue for screening of clinical drugs against continuous infection of KSHV. This research was accomplished by doctoral candidates He Zhiheng, Liu Yunhua, Liang Deguang and Wang Zhuo with instruction from Prof. Lan He.

New Solution for Anti-leukemia and Anti-tumor Drugs

Recently, Ding Ke Research Group of the Guangzhou Institute of Biomedicine and Health, CAS made progress in chemical synthetic methodology. They ingeniously applied drug design technology in the development of ligand for Ullmann coupling reaction. Through analysis of the structural characteristics of chemical ligands that can accelerate Ullmann coupling reaction as reported, they successfully designed 2-pyridine–βketones as a new ligand that can effectively accelerate different types of copper-catalyzed Ullmann coupling reactions under room temperature (25℃), thus providing an effective method for synthesis of natural products and drugs. The new ligand designed by Ding Ke Research Group can accelerate different types of copper-catalyzed Ullmann coupling reactions under room temperature. This reaction can tolerate hydroxy, amino, carbonyl, ester, cyan and many other active functional groups and apply to heteroaromatic system, which greatly expand the applicable scope of copper-catalyzed Ullmann coupling reaction. The result of their research not only provides an effective method for the preparation of aromatic amine, aromatic ether and other important chemical intermediates, but also applies to the synthesis of natural products and drugs with important biological activity. Currently, this catalytic system has been successfully applied in the synthesis of anti-leukemia drug Nilotinib and other anti-tumor drugs. Relevant results of research were published in Chem. Commun., Adv. Synth. Cat., J. Org. Chem., SynLett and other international academic journals and invention patents have been applied in China.

A Blank of World Biodiversity Filled

In September 2009, the comprehensive survey of plant diversity in the Hengduan mountain areas jointly carried out by Chinese and American scientists was formally completed after 6 years. Sun Hang, leader of the Chinese investigation team and Associate Director General of the Kunming Institute of Botany, CAS hoped that six years’ investigation of the Hengduan mountain areas could provide valuable data for in-depth understand and research of plant and fungi group in the Hengduan mountain areas. In 2003, the Kunming Institute of Botany signed an S&T cooperation agreement with the Harvard University Herbaria in Kunming to jointly carry out a cooperation project “research of origin and evolution of plant diversity in southwest China”. Promoted by Chinese and American botanic communities, the cooperation project won financial support from the Natural Science Foundation (NSF) “research of diversity of higher plants and fungi in southeast Tibet and west Sichuan” and the major international cooperation project of the Natural Science Foundation of China (NSFC) “research of origin and evolution of plant diversity in transverse mountain areas”. Since then, led by Chinese chief scientist Prof. Sun Hang from the Kunming Institute of Botany, CAS and American chief scientist David Boufford from the Harvard University, the China-US joint investigation team carried out five large-scale field scientific survey in nearly 50 counties located in Changdu of Tibet, Diqing of Yunan and Liangshan, Ganzi and Aba of Sichuan respectively. The survey team consisted of over twenty researchers from the Kunming Institute of Botany, CAS, the Institute of Botany, CAS, the Yunnan Normal University, the Harvard University, the Field Museum and the Kochi Prefectural Makino Botanical Garden, Japan. In the past six years, scientists from China and the United States collected 12,000-15,000 specimen and over 6,000 species of higher plants and fungi, established a plant picture and description online database open to scientists from all over the world and complied an online Chinese gazetteer, which provides an important reference for accurate identification of the place of collection of relevant plant samples.

Wild Species Germplasm Bank Established

On Nov. 24, a national check and acceptance conference on the project of “Southwest China Germplasm Bank of Wild Species” (“Germplasm Bank”) was held at the Kunming Institute of Botany, CAS. Some officials from the central and local government were present at the conference. Zhan Wenlong, Vice President of CAS and experts from relevant institutions also attended. The cold stores, drying compartments, walk-in culturing room and other facilities, germplasm resource database, information sharing management system, an unified technological system and scientific research platform integrated with functional gene test, clone and verification, and a Germplasm Resource Collection Center, Molecular Biology Experimental Center and Plant Germplasm Resources and Genomics Research Center have been all established in accordance with international standards. This project has so far obtained many types of important wild germplasm resources at home and abroad, including seeds, in vitro plant, animal cells, bacterial strain, DNA and etc. It has collected 8,444 species and 74,641 pieces of wild germplasm resources, including 252 species and 590 pieces of wild plant seeds from 21 countries. The Germplasm Repository has collected 437 species and 49,580 pieces of wild germplasm resources. As the first national germplasm bank of wild species, with investment totals 148 million RMB yuan and with such strong storage and research ability, the Germplasm Bank forms one of two germplasm banks for wild species in the world.