S-2-1 S. Ohta (Department of Bioscience, Fukui Prefectural University)
A report on the international cooperative field research project, Fukui Prefectural University Agro-ecological Exploration in Southwest Eurasia (FASWE)

International cooperative field research projects are proceeding in Turkey and Iran with the financial support by the JSPS (Grant-in-Aid No. 15255012). The aim is to clarify interrelationships among environments, people, crops, their wild relatives and weeds in the agricultural system based on wheat and barley. In Turkey, cooperation is carrying out with Dr. Hakan Ozkan, Cukurova University. Southeastern Turkey was surveyed in 2003 and 2004. Allopatry of the two intraspecific taxa in Aegilops neglecta and dimorphism of seed dormancy in Aegilops species were revealed. In Iran, Dr. Javad Mozafari, National Plant Gene-Bank of Iran, cooperates with us. The Caspian Sea coast and the Zagros Mountains were surveyed in 2003 and 2004. Allopatry of the three intraspecific taxa in Ae. tauschii and geographical distribution of Secale cereale with brittle and non-brittle spikes were revealed. Intraspecific genetic diversity in crops, their wild relatives and weed species will be studied until March of 2007.

S-2-2 K. Kato (Faculty of Agriculture, Okayama University)
Field study on genetic diversity of wheat in East Asia

China is diversified in topographical features and climate, ranged from 150 m below sea level to 4000 m above sea level, from 5.8°C to 26.4°C in average annual temperature, and 4 mm to 6558 mm in average annual precipitation (Li et al. 1998). Reflecting such diversity, different types of wheat are cultivated in respective areas in China. To uncover genetic diversity among wheat and barley landraces in and around China, field study has been carried out in Tibet (1995, 1996,1998), Shaanxi (1998, 1999) and Yunnan (2004), China, in Nepal and Bhutan (1999), and in India (2004). These field studies have been carried out as one of the activities of research projects entitled as "Genetic assay and study of crop germplasm in and around China" and "The development of sustainable biological production technologies harmonized with regional environmental conditions in East Asia", both of which were supported by a Grant-in-Aid of Ministry of Education, Science, Culture and Sports, Japan.

Symposium III.
Insight from chromosome research

S-3-1 T. Wako (Department of Biochemistry, National Institute of Agrobiological Sciences)
Histone code for chromosome structure and function

Control of gene expression is essential for improvement of crop production, such as expression of useful endogenes and/or transgenes, and repression of harmful endogenes and transposable elements. For this purpose, not only effective DNA code such as useful genes and regulatory elements but also histone code should be investigated. Histone code is defined certain combinations of post-translational modifications in nucleosomal histories. It affects chromosome and chromatin structure, and regulates epigenetically various cellar functions such as gene transcription. To reveal historic code for chromosome structure and function, the dynamics of histone H4 acetylation at lysine residues in barley mitotic chromosome was analyzed by using three-dimensional immunofluorescent method Pair-wise dynamics of historic acetylation were observed at nucleolar organizing regions and distal regions of chromosome in stage-specific manner. These pair-wise acetylations may regulate chromosome structure and function during mitosis as historic code.

S-3-2 K. Nagaki (Research Institute for Bioresources, Okayama University)
Exploration into the last frontiers of complex eukaryotic genomes

Centromeres are the last frontiers of higher eukaryotic genomes, consisting of highly repeated sequences that resist mapping, cloning and sequencing. Since it was believed as the centromeres are heterochromatic and do not contain any important active genes, the regions were left out from genome projects. We analyzed the regions in Arabidopsis and maize, and found that tandem repeats are functional. However, we could not know entire structure of the centromeres and size of the functional region because of the difficultness. The centromere of rice Chromosome 8 (Cen8) is a good example to know them. The Cen8 has an unusually low abundance of highly repetitive satellite DNA, which allowed its sequence to be determined. A ∼750 kb region within the Cen8 binds rice CENH3, the centromere-specific H3 histone. The CENH3 binding region is contained within a larger heterochromatin. Surprisingly, we found fourteen predicted and four active genes in the CENH3 binding region.