Many functional glycoproteins are expressed on the lymphocyte cell surface. Some of them carry O-linked oligosaccharides (O-glycans), which are conjugated through serine or threonine residues. During various biological processes, including T-cell activation, a tetrasaccharide on the T-cell surface is dramatically converted to a branched hexasaccharide, called core2 O-glycan. The same structural change in O-glycans is also found on the lymphocytes from patients with immunodeficiency conditions such as Wiskott-Aldrich syndrome and AIDS. Several studies revealing the roles of core2 O-glycans in immune (...) responses show that this is a biologically significant change. In particular, core2 O-glycans expressed on the cell surface reduce cell–cell interactions, thereby regulating immune responses. Furthermore, core2 O-glycan is a key backbone structure in forming selectin ligands. Thus, O-linked oligosaccharides, in particular those containing core2 branches, play vital roles in immune responses and may play dual roles in certain situations. This review will summarize the results obtained from various studies investigating the roles of O-glycans in immunological processes. BioEssays 23:46–53, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

Many functional glycoproteins are expressed on the lymphocyte cell surface. Some of them carry O-linked oligosaccharides (O-glycans), which are conjugated through serine or threonine residues. During various biological processes, including T-cell activation, a tetrasaccharide on the T-cell surface is dramatically converted to a branched hexasaccharide, called core2 O-glycan. The same structural change in O-glycans is also found on the lymphocytes from patients with immunodeficiency conditions such as Wiskott-Aldrich syndrome and AIDS. Several studies revealing the roles of core2 O-glycans in immune (...) responses show that this is a biologically significant change. In particular, core2 O-glycans expressed on the cell surface reduce cell–cell interactions, thereby regulating immune responses. Furthermore, core2 O-glycan is a key backbone structure in forming selectin ligands. Thus, O-linked oligosaccharides, in particular those containing core2 branches, play vital roles in immune responses and may play dual roles in certain situations. This review will summarize the results obtained from various studies investigating the roles of O-glycans in immunological processes. BioEssays 23:46–53, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

教養と学問が関係することは、実は自明ではない。教養とは何か。また学問と思想はどのように関わるのか。知識人として、学者として、丸山が発し続けた問いと思考の展開を、遺された言葉の総体から精緻に読み解き、「 丸山論」をこえて現代日本に提示。.

The exocyst is a conserved octameric complex that physically tethers a vesicle to the plasma membrane, prior to membrane fusion. It is important not only for secretion and membrane delivery but also, in mammalian cells, for cytokinesis, ciliogenesis, autophagy, tumorigenesis, and host defense. The combination of genome editing and advanced light microscopy of exocyst subunits in living cells has recently shown the complex to be much more dynamic than previously appreciated, and exposed how little we still know about its function (...) and regulation. (shrink)

Over the last few years, I have attended several political meetings concerned with the refugee crisis, multiculturalism or Indigenous rights in Australia, meetings at which liberal democratic–minded ‘left-wing’ people came together to discuss, or agitate for change in, governmental policies. At these meetings, I always found it difficult to accept the slogans on their placards and in their speeches: ‘Shame Australia! Reconciliation for a united Australia’, ‘Wake up Australia! We welcome refugees!’ or ‘True Australians are tolerant! Let’s celebrate multicultural Australia!’ (...) My uncomfortable feeling came not only from the fact that I was left out because of my Japanese nationality but also because I had never seen or heard words like ‘shame Japan’, ‘wake up Japan’ or ‘true Japanese are...’ at Japanese ‘left-wing’ political gatherings. In Japan, these are words used only by right-wing nationalists. Indeed it is difficult to even imagine liberal-left intellectuals in postwar Japan calling for a ‘true Japanese’ political response, such is the extent to which the idea of ‘good nationalism’ is now regarded as an oxymoron. This is my starting point for an essay in which I want to be attentive to the different roles played by national in the Japanese and Australian political environments. (shrink)

Egg or sperm? The mechanism of sexual fate decision in germ cells has been a long‐standing issue in biology. A recent analysis identified foxl3 as a gene that determines the sexual fate decision of germ cells in the teleost fish, medaka. foxl3/Foxl3 acts in female germline stem cells to repress commitment into male fate (spermatogenesis), indicating that the presence of mitotic germ cells in the female is critical for continuous sexual fate decision of germ cells in medaka gonads. Interestingly, foxl3 (...) is found in most vertebrate genomes except for mammals. This provides the interesting possibility that the sexual fate of germ cells in mammals is determined in a different way compared to foxl3‐possessing vertebrates. Considering the fact that germline stem cells are the cells where foxl3 begins to express and sexual fate decision initiates and mammalian ovary does not have typical germline stem cells, the mechanism in mammals may have been co‐evolved with germline stem cell loss in mammalian ovary. (shrink)