DNA manipulation and data analyses
Manipulation of genomic DNA and plasmids and DNA cloning were performed as described by Sambrook and Russell (2001). Restriction enzymes (TaKaRa) were used for DNA digestion and modification. DNA sequencing was performed by Macrogen (Seoul). DNA sequences were analyzed with the BLAST program at the National Center for Biotechnology Information (Gish and States, 1993), MEGALIGN (DNASTAR, Madison, WI, USA), and GENETYX-WIN software (Genetyx).