LINKAGE MAPPING OF STARCH BRANCHING ENZYME-III IN RICE (ORYZA-SATIVA L) AND PREDICTION OF LOCATION OF ORTHOLOGOUS GENES IN OTHER GRASSES

The chromosomal position of Starch Branching Enzyme III (SBEIII) was d etermined via linkage to RFLP markers on an existing molecular map of rice (Oryza sativa L.). A cDNA of 890 bp was generated using specific PCR primers designed from available SBEIII sequence data and used as a probe in Southern analysis. The SBEIII cDNA hybridized to multiple re striction fragments, but these fragments mapped to a single locus on r ice chromosome 2, flanked by CD0718 and RG157. The detection of a mult iple-copy hybridization pattern suggested the possibility of a tandeml y duplicated gene at this locus. The map location of orthologous SEE g enes in maize, wheat, and oat were predicted based on previously publi shed genetic studies and comparative maps of the grass family.