CLONING AND MOLECULAR CHARACTERIZATION OF A NOVEL CHROMOSOME-SPECIFICCENTROMERE SEQUENCE OF CHINESE-HAMSTER

We isolated and characterized the first chromosome-specific satellite DNA (HC2sat) of Chinese hamster. This novel satellite was localized to the pericentric region of hamster chromosome 2. The 2.8 kb long repea t unit of HC2sat was identified and two such units were sequenced. Ext ended short range periodicity could not be revealed in repeat units. T hese elements are amongst the largest satellite repeat units reported from mammals to date. HC2sat is a major constituent of the pericentric region of CHO chromosome 2 representing a 7-14 Mb long DNA segment. S tudies of long range organization of HC2sat indicated that the formati on of the satellite array might occur in different phases and involved different amplification mechanisms.