Cellular response of Parachlorella kessleri to a solid surface culture environment

Attached culture allows high biomass productivity and is a promising biomass cultivating system because neither a huge facility area nor a large volume of culture medium are needed. This study investigates photosynthetic and transcriptomic behaviors in Parachlorella kessleri cells on a solid surface after their transfer from liquid culture to elucidate the physiological and gene-expression regulatory mechanisms that underlie their vigorous proliferation. The chlorophyll content shows a decrease at 12 h after the transfer; however, it has fully recovered at 24 h, suggesting temporary decreases in the amounts of light harvesting complexes. On PAM analysis, it is demonstrated that the effective quantum yield of PSII decreases at 0 h right after the transfer, followed by its recovery in the next 24 h. A similar changing pattern is observed for the photochemical quenching, with the PSII maximum quantum yield remaining at an almost unaltered level. Non-photochemical quenching was increased at both 0 h and 12 h after the transfer. These observations suggest that electron transfer downstream of PSII but not PSII itself is only temporarily damaged in solid-surface cells just after the transfer, with light energy in excess being dissipated as heat for PSII protection. It thus seems that the photosynthetic machinery acclimates to high-light and/or dehydration stresses through its temporal size-down and functional regulation that start right after the transfer. Meanwhile, transcriptomic analysis by RNA-Seq demonstrates temporary upregulation at 12 h after the transfer as to the expression levels of many genes for photosynthesis, amino acid synthesis, general stress response, and ribosomal subunit proteins. These findings suggest that cells transferred to a solid surface become stressed immediately after transfer but can recover their high photosynthetic activity through adaptation of photosynthetic machinery and metabolic flow as well as induction of general stress response mechanisms within 24 h

Additional file 1: Table S1. of Cell type-specific effects of p27KIP1 loss on retinal development

Antibodies. Table S2. Primers. (DOCX 17 kb

分子遺伝子学を導入したロコモティブシンドローム疫学調査

application/pdf高齢化の進行する本邦において、運動器の障害のために移動能力の低下をきたすロコモティブシンドローム（ロコモ）が、注目を浴びている。今回、高齢化の進行した山村を対象とし、ロコモに関する疫学研究を行った。 本研究により画像上の骨粗鬆症、変形性膝関節症、椎体骨折よりも膝痛・腰痛といった症状の方がロコモに影響を与えていること、大腿四頭筋筋力がロコモに関連すること、25～50歳の時の運動習慣が高齢になってからのロコモに関連することが分かった。画像上の疾患があろうとも膝痛・腰痛といった症状をコントロールすること、若年時より運動習慣を持ち、大腿四頭筋筋力を維持することでロコモを予防出来る可能性が示唆された。Due to the increase in the percentage of elderly Japanese people, the percentage of the population that needs nursing care is increasing. The concept of locomotive syndrome (LS) has been proposed to describe the risk of mobility dependence caused by various motor organ disorders. Thus, we performed an epidemiological study about LS among Japanese old residents. Knee pain and/or low back pain had more strongly relationship with LS than radiographic knee osteoarthritis, osteoporosis, and vertebral fractures. Poor quadriceps muscle power was related to LS. Participants who reported regular exercise habits in middle age had better physical function during old age. To control physical pains such as knee pain and/or low back pain, to maintain quadriceps muscle power, and regular exercise habits in middle age appear to protect against LS during the older years.2015年度～2017年度科学研究費補助金(基盤研究(C))研究成果報告書15K0873