Chii-Shiarng Chen   

Professor (Director)
Ph.D., University of Texas at Austin, 1993

Marine Cell and Developmental Biology;

Cnidarian Endosymbiosis
email: cchen@nmmba.gov.tw
phone (886) 8-882-5040 or
(886) 8-882-5001 ext 1363, 1361
fax (886) 8-882-5087

Research Interest: 
Marine Cell Biology  Regulatory mechanism of marine endosymbiosis in Cnidarian-dinoflagellate association remains unknown.  In order to investigate cellular and molecular interactions between symbionts and their host endoderm cells, homogeneous population of endoderm cell is prerequisite.  Nevertheless, isolation of homogeneous endoderm cells has been unsuccessful for the past decades.  Without continual efforts to efficiently isolate endoderm cells for in vitro studies and establishment of cell cultures, there is no promise for a full understanding on the mechanism of endosymbiosis. 

We are currently focuses on investigating regulatory mechanism of endosymbiosis in isolate endoderm cells from a stony coral Euphyllia glabrescens. By using imaging analyses, Pulse-Amplitude-Modulated (PAM) microscopy and various cellular and molecular techniques, we now show that  symbiont photosynthetic activity is finely tuned depending on the symbiotic status. Molecules, including genes, proteins and membrane lipids, that responsible for this regulation are being investigated.

Marine Developmental Biology Mechanism for initial dinoflagellate acquisition during embryonic development in cnidaria remains unclear. Two modes of initial symbiont acquisition in cnidaria have been proposed, including horizontal and vertical transmission. In most brooders, i.e. corals whose larvae develop within parental polyps and release zooxanthellate planulae in due time, are termed vertical transmission because zooxanthellae in parental gastrodermal cells are transferred from mother colonies to the oocyte or planula. Symbionts residing inside the egg or planula then proliferate in accord with the developmental process. Nevertheless, critical questions arise regarding to mutual effects between state of endosymbiosis and coral development. For example, how the distribution of intracellular zooxanthellae is regulated during the early cleavage and germ layer formation? How these maternal-derived zooxanthellae recognize their final destination and end up in the endodermal layer? Starting from organism level, we are examining and the cellular and molecular effects of intracellular symbionts on host animal development.

Selected Publications: 

1. Chen, C.-S., C.-C. Yeh, H.-P. Lin and L.-S. Fang. 2005. The use of a fluorescent membrane probe to identify zooxanthellae in hospite among dissociated endoderm cell culture from coral. Protoplasma (SCI, in press).

2. Özçelik S, G Orr, D Hu, C.-S. Chen, H Resat, G Harms, L Opresko, S Wiley, and S Colson. 2004. “FRET measurements between small numbers of molecules identify subtle changes in receptor interactions.“ Photonics West Proceedings, International Society for Optical Engineering 5323:119-127 (SCI).

3. Chen, C.-S. 2002. Phorbol ester induces elevated oxidative activity and alkalization in a subset of lysosomes. BMC Cell Biology 3:21 (6 August, 2002) (SCI).

4. Chen, C.-S. and K. R. Gee. 2000. Redox-dependent trafficking of 2,3,4,5,6-pentafluorodihydrotetramethylrosamine, a novel fluorogenic indicator of cellular oxidative activity. Free Radic. Biol. & Med.  28 (8), 1266-1278. (SCI)

5. Chen, C.-S., W.-N. U. Chen, M. Zhou, S. Arttamangkul, and R. P. Haugland. 2000. Probing the cathepsin D using a BODIPY FL-pepstatin A: applications in fluorescence polarization and microscopy. J. Biochem. Biophys. Methods  42 (3), 137-151. (SCI)

6. Chen, C.-S., M. C. Patterson, C. L. Wheatley, J. F. O’Brien and R. E. Pagano. 1999. Broad screening test for sphingolipid-storage diseases.  Lancet  354 (9182), 901-905. (SCI)

7. Pagano, R. E., R. Watanabe, C. Wheatly, and C.-S. Chen. 1999. Use of N-[5-(5,7-dimethyl boron dipyrromethene difluoride]-sphingomyelin to study membrane traffic along the endocytic pathway. Chemistry and Physics of Lipids 102, 55-63. (SCI)

8. Diwu, Z., C.-S. Chen, C. Zhang, D. H. Klaubert and R. P. Haugland. 1999. A novel acidotropic dual-excitation and dual-emission pH indicator and its potential application in labeling acidic organelles of live cells. Chemistry and Biology 6, 411-418. (SCI)