WORKING IN CONCERT:Courtesy Katherine L. Knight and Ki-Jong Rhee © 2004 American Association of ImmunologistsLeft is a section of appendix following introduction of Bacteroides fragilis; right is a section of appendix following introduction of B. fragilis plus Bacillus Subtilis. B. fragilis alone results in no gut-associated lymphoid tissue (GALT) development while the combination shows a B lymphocyte follicle (red dots).Commensal or nonpathogenic bacteria have established a mutually benefi

SYNAPTIC MITOCHONDRIA:Courtesy of Husseini ManjiThe surge in intracellular calcium during an individual action potential is rapidly buffered by mitochondrial calcium uptake. The release of calcium back into the cytoplasm is believed to allow for post-tetanic potentiation. ATP-production is essential for vesicle docking, fusion and endocytosis. Mitochondrial pathology and some treatments affect the mitochondrial membrane potential. Disrupting the MMP results in more pronounced calcium spikes; cha

Courtesy of Jessica BonameLike the impossibly well-funded thieves from a good heist film, viruses pull immune-escape strategies from a deep bag of tricks. Murine γ-herpesvirus-68 (MHV-68) fine-tunes its attack on MHC class I molecules by degrading components of the complex that loads them with peptides.1"There's the primary targeting of the class I heavy chain," says Jessica Boname, in Philip Stevenson's lab at the University of Cambridge, who showed previously that MHV-68's MK3 protein dir

Courtesy of Eric Robert RussellRecent gene-expression findings may energize the search for a mechanism in bipolar disorder pathology. Chris-tine Konradi and collaborators, from McLean Hospital, Belmont, Mass., and Harvard Medical School, showed that of 43 genes downregulated in brain specimens from subjects with bipolar disorder, 18 encode mitochondrial proteins.1 These results bolster a hypothesis put forth almost four years ago by Tadafumi Kato, currently at the RIKEN Brain Research Institute

Courtesy of Lars FuggerParadoxically, a single MHC class II allele, HLA-DQ0602, confers susceptibility to narcolepsy but prevents development of type I diabetes. Clinical immunologist Lars Fugger and structural biologist Yvonne Jones, both at Oxford University, have compared the crystal structure of the allele with those of two similar MHC molecules that respectively predispose to type 1 diabetes and protect against narcolepsy.1 They have identified unique features of several pockets within the