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Heterochromatin protein 1s (HP1s) are nonhistone chromosomal proteins that play a direct role in the formation and maintenance of heterochromatin structure. Similarly to Caenorhabditis elegans, silkworms possess holocentric chromosomes, in which diffused kinetochores extend along the length of each chromosome. We have isolated two silkworm HP1 homologues, BmHP1a and BmHP1b. Cytological analysis showed a unique localization of BmHP1s during cell division, in which these proteins first appear to dissociate from the chromosomes, but then return to enclose the chromosomes during metaphase. BmHP1s formed homo- and hetero-dimers and interacted with BmSu(var)3-9, which is a methyltransferase for histone H3 lysine 9 (H3K9). We further showed, using a silkworm cell-based reporter system, that BmHP1b had higher transcriptional repression activity than BmHP1a, whereas BmHP1a interacted more strongly with BmSu(var)3-9 than did BmHP1b. These results suggest that silkworm HP1a and HP1b may play different roles in heterochromatin formation in holocentric silkworm chromosomes.

Epigenetic information is encoded in post-translational modifications (PTMs) of histones. Various combinations of these marks contribute to the regulation of chromatin-templated DNA metabolisms. The histone code is gradually translated into biological responses in model organisms. However, in the silkworm, the modifications of histones with unique holocentric chromosomes have not yet been analyzed. TAU-PAGE analysis of the silkworm histone variants H2A, H2B, and H3, separated by RP-HPLC, suggested silkworm specific modification. Detailed mass spectrometry analyses of the peptides derived from the N-terminus of the silkworm H3.2 generated by glutamyl endopeptidase, lysyl endopeptidase, and trypsin digestions revealed global modifications around H3K9.

The HPLC method is now commonly used for fractional determination of chlorogenic acid (Chl). We determined the quantity of Chl (5 -CQA + 3 -CQA) contained in raw coffee beans, and examined the influence of different roasting times and extraction conditions (temperature, device, water). The results were as follows:(1) Raw coffee beans contained 4.5 to 6.0% of Chl. This Chl was reduced by roasting, that is, about 60% of Chl was lost by mild roasting, 60 to 70% by moderate roasting, 70 to 80% by moderate to strong roasting, and 90 to 99% by strong roasting.(2) The influence of temperature on the extraction of Chl was slight, but the quantity of Chl extracted tended to be slightly higher at 95°C, followed in a descending order by 90°C and 85°C.(3) The quantities of Chl extracted by a spirit lamp siphon and paper drip were the same, while that extracted by an electric coffee maker was smaller.(4) The quantities of Chl extracted with distilled water and soft water were the same, but that extracted with hard water was smaller.

ゆで調理における塩の添加・利用に関するアンケート調査を, 2001年9月下旬～10月上旬に, S短期大学生, その親園児の親に対して行った。その結果, 以下のことが明らかになった。1) 調理の学習経験では, 学生は学校や親から学んだと言う回答が多く, 園児親および学生親は学校以外に親, そしてマスメディアで学んだ割合が高かった。親から学んだとする割合は全体で60%前後, 園児親, 学生親がマスメディアで学んだ割合は約53%であった。2) 青菜の喫食状況は学生親は100%だったが, 若い世代では92～97%だった。その調理方法は「ゆでる」が多かった。3) 青菜のゆで量と水量については, たっぷりの水量を使用している人が多かったが, 学生はゆで量の約10倍量の水を, 学生親はそれ以上の水を使用する傾向がみられた。4) ほうれんそうのゆで調理における塩の使用はいずれの場合もほとんどがひとつまみ程度で, その濃度は0.1%以下であった。5) 塩添加の目的は「色を良くする」が多く, 次いで「あく抜き」であった。しかし, 現状の塩の使用量では「あく抜き」の効果が得られているとは考えられない。6) 塩添加の知識の取得源は, 親, 学校という回答が多かった。7) いずれの世代も, ゆでる物, ゆでる量, そしてそれにふさわしい水量, 塩の使用の有無などを良く考えずにゆで調理を行っており, それが親から子へ受け継がれていることが推察された。

The amount of dietary fiber (neutral detergent fiber, acid detergent fiber and lignin) in the edible portion; leaf, stalk and bud; of 53 species of wild plants was determined by Van Soest method and also the amounts of crude fiber, water, fat and ash of these plants were estimated. These plants were taken in Fukushima prefecture and belonged to Compositae, Liliaceae, Umbelliferae, Polypodiaceae, Araliaceae, Cruciferaeae, Uruticaceae, Polygonaceae, Caprifoliaceae, Equisetaceae, Rosaceae, Lardinabalaceae, Campanulaceae, Leguminosae, Chenopodiaceae, Saururaceae, Plantaginaceae, Berberidaceae, Saxifragaceae, Rutaceae, Gramineae, Actinidiaceae and Clethraceae.Takadiastase digestion of plant before analysis of neutral detergent fiber had little effect on the amount of neutral detergent fiber in leaf, stalk and bud of wild plants. The amounts of neutral detergent fiber, acid detergent fiber and crude fiber of these plants were 1.07 to 5.92%, 0.79 to 5.19% and 0.64 to 3.67% respectively. The correlation (r) of c ude fiber with neutral detergent fiber, acid detergent fiber and cellulose; the difference between acid detergent fiber and lignin; were 0.63, 0.65 and 0.77 respectively. Neutral detergent fiber had a little correlation with nitrogen free extract (r=-0.64) but no correlation with protein and ash (r=-0.24, 0.22).