Korea University, Korea
Prof. Joon Kim has completed his BS and MS in Microbiology from Seoul National University, PhD in Biochemistry from the University of California at Berkeley and postdoctoral study from Harvard Medical School. He is a Professor in the Division of Life Sciences, and the Director of Radiation Safety and Management Center, Korea University, Seoul, Korea. He has published more than 150 papers in reputed journals
Ribosomal protein S3(rpS3) is a component of the 40S ribosomal small subunit but has multiple other extra-ribosomal functions like apoptosis, cell cycle control, DNA repair etc. It has a DNA repair endonuclease activity which is related with various cancers. Recently, we have discovered that this protein is secreted only from various cancer cell lines as a homodimer but not in normal cells. We also confirmed that rpS3 is secreted more into media from the more invasive cancer cell lines. Presently we confirmed that the secreted protein is glycosylated at the Asn 165 residue and point mutation on this site is defective for the secretion. The secretion pathway turned out to be a ER-Golgi dependent pathway. We propose that glysosylated rpS3 could be used as a useful cancer marker.