• Korean Journal Plant Pathology
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• v.14 no.5
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• pp.382-385
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• 1998

Molecular identification and genetic relationships between a phytoplasma associated with chestnut little leaf (CLL) and phytoplasma isolates of other trees in Korea were amplified by polymerase chain reaction (PCR). These 16S rDNA sequences amplified from the various phytoplasmas were used in DNA heteroduplex mobility assays (HMA). In DNA HMA combined with PCR, the mobility shift was observed for a heteroduoplex formed in combined with CLL and jujube witches broom, but not for those formed in combined with CLL and each of sumac witches broom, paulownia witches broom, and mulberry dwarf. HMA combined with PCR has been shown to be a very useful method for detection and differentiation of phytoplasmas.

• The Plant Pathology Journal
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• v.18 no.6
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• pp.308-312
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• 2002

Heteroduplex mobility assay (HMA) and single-strand conformation polymorphism (SSCP) analyses combined with PCR were developed for genetic differentiation of various phytoplasma isolates. In the HMA and SSCP analyses, differences in the mobility shifts and the SSCP band patterns identified three distinct types of phyto-plasmas: Type Ⅰ, jujube witches'-broom (JWB) and ligustrum witches'-broom (LiWB); Type Ⅱ, mulberry dwarf（MD) and sumac witches'-broom (SuWB); and Type Ⅲ, paulownia witches'-broom (PaWB). Results of the sequence analyses revealed that phytoplasmas of JWB and MD had 100％ homology with LiWB and SuWB, respectively. On the other hand, PaWB phyto-plasma had 97.8% homology with MD phytoplasma. The PCR-HMA and SSCP techniques were very useful in determining variations in sequence among several isolates of phytoplasmas. Furthermore, the methods were rapid, economical, highly sensitive, and easy to handle with the gels.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2002.11a
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• pp.127.1-127
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• 2002

• BMB Reports
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• v.38 no.6
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• pp.690-694
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• 2005

Transcription termination of the human mitochondrial genome requires specific binding to termination factor mTERF. In this study, mTERF was produced in E. coli and purified by two-step chromatography. mTERF-binding DNA sequences were isolated from a pool of randomized sequences by the repeated selection of bound sequences by gel-mobility shift assay and polymerase chain reaction. Sequencing and comparison of the 23 isolated clones revealed a 16-bp consensus sequence of 5'-GTG$\b{TGGC}$AGANCCNGG-3' in the light-strand (underlined residues were absolutely conserved), which nicely matched the genomic 13-bp terminator sequence 5'-$\b{TGGC}$AGAGCCCGG-3'. Moreover, mTERF binding assays of heteroduplex and single-stranded DNAs showed mTERF recognized the light strand in preference to the heavy strand. The preferential binding of mTERF with the light-strand may explain its distinct orientation-dependent termination activity.