ASU SoLS Faculty: Jiunn-Liang Chen

Dr. Chen received a Ph.D degree from Indiana University, Bloomington in 1997. He was a postdoctoral fellow at Johns Hopkins University before he joined the SoLS faculty at ASU. He also holds a joint appointment in the Department of Chemistry & Biochemistry.

We are interested in understanding the structure, function and evolution of ribonucleoprotein (RNP) complexes in cells. Our attention currently focuses on the telomerase RNP enzyme, a unique reverse transcriptase essential for maintaining telomere length in most eukaryotes. Telomeres act as caps at the ends of chromosomes, and are required for chromosome stability.

Telomerase elongates telomere length by adding telomeric repeats to chromosome ends to counterbalance the natural shortening that occurs during DNA replication. Because of its role in chromosome stability, telomerase regulation is a critical step in tumorigenesis and aging. To maintain chromosome stability and infinite growth, telomerase is activated in immortal cells such as stem cells, germ line as well as 90% of human tumors. Moreover, patients with dyskeratosis congenita, a disease of premature aging, carry a mutation in the telomerase RNA (TR) or the telomerase reverse transcriptase protein (TERT) genes.

Elucidation of the molecular mechanism of telomerase function is the main goal of our lab and will have significant medical implications in cancer and aging. Our goals are to understand (1) how telomerase RNP is assembled and regulated in cells, (2) how different components of the complex participate in the regulation of telomerase function, and (3) how this RNP complex evolved in different eukaryotes. Our research employes a variety of approaches involving biochemical and biophysical techniques, as well as molecular genetics and molecular biology.

Selected Publications

Armanios, M., J.L. Chen, Y.-P.C. Chang, R.A. Brodsky, A. Hawkins, C.A. Griffin, J.R. Eshleman, A. Chakravarti, A. Hamosh and C.W. Greider (2005) "Haploinsufficiency of hTERT leads to anticipation in autosomal dominant dyskeratosis congenital," Proc. Natl. Acad. Sci. U.S.A. 102 15960-15964.

Chen, J.L. and C.W. Greider (2005) "Telomerase biochemis try and biogenesis," Telomeres-2nd edition 49-79.

Chen J.L. and C.W. Greider (2005) "Functional analysis of the pseudoknot structure in human telomerase RNA," Proc. Natl. Acad. Sci. U.S.A. 102 8080-8085.

Chen J.L. and C.W. Greider (2004) "Telomerase RNA structure and function: implications for dyskeratosis congenita," Trends in Biochemical Sciences 29 183-192.

Chen J.L. and C.W. Greider (2004) "An emerging consensus for telomerase RNA structure," Proc. Natl. Acad. Sci. U.S.A. 101 14683-14684.

Chen J.L. and C.W. (2003) Greider"Determinants in mammalian telomerase RNA that mediate enzyme processivity and cross-species incompatibility," EMBO J. 22 304-314.

Chen, J.L. and C.W. Greider (2003) "Template boundary definition in mammalian telomerase," Genes & Development 17 2747-2752

Chen, J.L., K.K. Opperman and C.W. Greider (2002) "A critical stem-loop structure in the CR4-CR5 domain of mammalian telomerase RNA," Nucleic Acids Research 30 592-597.

Thomas, B.C., A.V. Kazantsev, J.L. Chen and N.R. Pace (2000) "Photoaffinity cross-linking and RNA structure analysis," Methods in Enzymology 318 136-147.

Chen, J.L., M.A. Blasco and C.W. Greider (2000) "Secondary structure of vertebrate telomerase RNA.," Cell 100 503-514.

Chen, J.L., J.M. Nolan, M.E. Harris and N.R. Pace (1998) "Comparative photocross-linking analysis of the tertiary structures of Escherichia coli and Bacillus subtilis RNase P RNAs.," EMBO J. 17 1515-1525.

Chen, J.L. and N.R. Pace (1997) "Identification of the universally conserved core of ribonuclease P RNA.," RNA 3 557-560.

Harris, M.E., A.V. Kazantsev, J.L. Chen and N.R. Pace (1997) "Analysis of the tertiary structure of the ribonuclease P ribozyme-substrate complex by site-specific photoaffinity crosslinking.," RNA 3 561-576.