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学生による高齢者へのインタビューを通して,その生活の現状とこれまでの生活の歴史と考え方を調査した。インタビューをした高齢者は比較的健康で,現在の生活に満足している。約30%の人が現在でも仕事をしている。これまでの仕事歴は男性が専業,女性がパートとはっきり分かれているが,80%の人は女性が仕事をもつことはよいことだと考えている。介護の体験は女性が多いが,男性も28%は介護経験者である。介護して心に残った印象は,ただ辛いばかりでなく,介護・生・死についてさまざまな感慨を得ている。自分の老後に関しては男性がつれあい,女性が娘とはっきりと別れており,介護をしてもらう場所としては男女とも自宅がよいと回答している。この点ではともに全国的調査と同様の典型的なパターンではあるが,病院より老人ホームの方が高くなったり,家族以外の社会的介護が望ましいと思う人はともに19%前後とかなり高い値を示すなど,新しい傾向も垣間見られる。老人ホームはあまり好ましいとは思っていないが,それでも30%の人が見学に行ったり,行きたいと思っている。質問をした学生達には大切な仕事だから頑張ってとか,君なら大丈夫と温かい励ましをいただいており,高齢者とじっくり話し合うのは初めての経験という学生達はそれぞれに感銘を受けている

Friend of Prmt1, FOP is a novel component of the nuclear SMN complex isolated using biotin affinity purification

SMN (survival motor neuron protein) complexes are essential for the biogenesis of uridine-rich small nuclear ribonucleoproteins (UsnRNPs). During the biogenesis, the SMN complexes bound to UsnRNPs are transported from the cytoplasm to the nucleus, and moved to Cajal body (bodies)/Gems (Cajal/Gems) where the SMN complexes- UsnRNPs are subjected to additional chemical modifications and dissociated to the SMN complexes and the mature UsnRNPs. Although the mature UsnRNPs are assembled into spliceosome with newly transcribed pre-mRNA in the perichromatin fibrils at the chromatin, the role of the dissociated nuclear SMN complexes remains undetermined. In this study, we identified Friend of Prmt1 (FOP; chromatin target of Prmt1, CHTOP; C1orf77) as a novel component of the nuclear SMN complexes by the biotin affinity purification, coupled with the mass spectrometry-based protein identification. FOP was associated with SMN, Gemines 2, 3, 4, 6, and 8, unrip, and fragile X mental retardation 1 protein (FMR1), as well as with U5and U6 snRNAs in the nucleus, but not with Sm proteins, Gemin5, coilin, and U1 and U2snRNAs. Using the quantitative proteomic method with SILAC coupled with RNA interference, we also showed that FOP is required for the association of the SMN complexes with hnRNPs, histone proteins, and various RNA-binding proteins. It is reported that FOP localizes mainly in the nuclear speckles, binds chromatin, and plays a role in mRNA transcriptional regulation. Our present data suggest that the nuclear SMN complex containing FOP participates in the process of mRNA post-transcriptional regulation

Domain Organization, Catalysis and Regulation of Eukaryotic Cystathionine Beta-Synthases

Cystathionine beta-synthase (CBS) is a key regulator of sulfur amino acid metabolism diverting homocysteine, a toxic intermediate of the methionine cycle, via the transsulfuration pathway to the biosynthesis of cysteine. Although the pathway itself is well conserved among eukaryotes, properties of eukaryotic CBS enzymes vary greatly. Here we present a side-by-side biochemical and biophysical comparison of human (hCBS), fruit fly (dCBS) and yeast (yCBS) enzymes. Preparation and characterization of the full-length and truncated enzymes, lacking the regulatory domains, suggested that eukaryotic CBS exists in one of at least two significantly different conformations impacting the enzyme’s catalytic activity, oligomeric status and regulation. Truncation of hCBS and yCBS, but not dCBS, resulted in enzyme activation and formation of dimers compared to native tetramers. The dCBS and yCBS are not regulated by the allosteric activator of hCBS, S-adenosylmethionine (AdoMet); however, they have significantly higher specific activities in the canonical as well as alternative reactions compared to hCBS. Unlike yCBS, the heme-containing dCBS and hCBS showed increased thermal stability and retention of the enzyme’s catalytic activity. The mass-spectrometry analysis and isothermal titration calorimetry showed clear presence and binding of AdoMet to yCBS and hCBS, but not dCBS. However, the role of AdoMet binding to yCBS remains unclear, unlike its role in hCBS. This study provides valuable information for understanding the complexity of the domain organization, catalytic specificity and regulation among eukaryotic CBS enzymes.This work was supported by Postdoctoral Fellowship 0920079G from the American Heart Association (to TM), by National Institutes of Health Grant HL065217, by American Heart Association Grant In-Aid 09GRNT2110159, by a grant from the Jerome Lejeune Foundation (all to JPK) and by a research contract RYC2009-04147 (to ALP). In addition, grant support (P11-CTS-07187, CSD2009-00088 and BIO2012-34937) to Dr. Jose M. Sanchez-Ruiz (University of Granada) and SGIker technical and human support (UPV/EHU, MICINN, GV/EJ, ESF) are gratefully acknowledged