Early and extensive alterations of glial connexins, distal oligodendrogliopathy type demyelination, and nodal/paranodal pathology are characteristic of multiple system atrophy.

The pathological hallmark of multiple system atrophy (MSA) is aberrant accumulation of phosphorylated α-synuclein in oligodendrocytes, forming glial cytoplasmic inclusions (GCIs). Extensive demyelination occurs particularly in the olivopontocerebellar and striatonigral pathways, but its precise mechanism remains elusive. Glial connexins (Cxs), which form gap junction channels between astrocytes and oligodendrocytes, play critical roles in myelin maintenance, and have not been studied in MSA. Therefore, we immunohistochemically investigated glial Cx changes in the cerebellar afferent fibers in 15 autopsied patients with MSA. We classified demyelinating lesions into three stages based on Klüver-Barrera staining: early (Stage I), intermediate (Stage II), and late (Stage III) stages showing subtle, moderate, and severe myelin reduction, respectively. Myelin-associated glycoprotein, but not myelin oligodendrocyte glycoprotein, was preferentially decreased in Stage I, suggesting distal oligodendrogliopathy type demyelination. Accumulation of phosphorylated α-synuclein in oligodendrocytes was frequently seen in Stage I but less frequently observed in Stages II and III. Tubulin polymerization-promoting protein (TPPP/p25α)-positive oligodendrocytes were preserved in Stage I but successively decreased in Stages II and III. Even at Stage I, Cx32 was nearly absent from myelin, despite the relative preservation of other nodal proteins, such as neurofascin, claudin-11/oligodendrocyte-specific protein, and contactin-associated protein 1, which successively decreased in the later stages. Cx32 was re-distributed in the oligodendrocyte cytoplasm and co-localized with GCIs. Cx47 gradually decreased at the oligodendrocyte surface in a stage-dependent manner but was not co-localized with GCIs. Astrocytic Cx43 was down-regulated in Stage I but up-regulated in Stages II and III, reflecting astrogliosis. Cx43/Cx47 gap junctions significantly decreased from Stage I to III. Activated microglia/macrophages and T cells infiltrated in Stage I rather than Stages II and III. Therefore, early and extensive alterations of glial Cxs, particularly Cx32 loss, occur in MSA and may accelerate distal oligodendrogliopathy type demyelination and nodal/paranodal dysfunction through disruption of inter-glial communication.

Tracing the evolutionary history of blood cells to the unicellular ancestor of animals.

Blood cells are thought to have emerged as phagocytes in the common ancestor of animals followed by the appearance of novel blood cell lineages such as thrombocytes, erythrocytes, and lymphocytes, during evolution. However, this speculation is not based on genetic evidence and it is still possible to argue that phagocytes in different species have different origins. It also remains to be clarified how the initial blood cells evolved; whether ancient animals have solely developed de novo programs for phagocytes or they have inherited a key program from ancestral unicellular organisms. Here, we traced the evolutionary history of blood cells, and cross-species comparison of gene expression profiles revealed that phagocytes in various animal species and Capsaspora (C.) owczarzaki, a unicellular organism, are transcriptionally similar to each other. We also found that both phagocytes and C. owczarzaki share a common phagocytic program, and that CEBPα is the sole transcription factor highly expressed in both phagocytes and C. owczarzaki. We further showed that the function of CEBPα to drive phagocyte program in nonphagocytic blood cells has been conserved in tunicate, sponge, and C. owczarzaki. We finally showed that, in murine hematopoiesis, repression of CEBPα to maintain nonphagocytic lineages is commonly achieved by polycomb complexes. These findings indicate that the initial blood cells emerged inheriting a unicellular organism program driven by CEBPα and that the program has also been seamlessly inherited in phagocytes of various animal species throughout evolution.

[A case of anti-myelin oligodendrocyte glycoprotein (MOG) and anti-N-methyl-D-aspartate (NMDA) receptor antibody-positive encephalitis with optic neuritis].

A 20-year-old female was hospitalized due to generalized seizure two weeks after an infection. She reported disorientation, neck stiffness and weakness in her legs. MRI FLAIR images and T2WI on her first visit to our hospital showed hyperintense lesions in the bilateral cingulate gyrus and the medial region of the superior frontal gyrus. Gadolinium (Gd)-enhanced T1WI showed enhancement in the upper part of the corpus callosum. Examination of her cerebrospinal fluid (CSF) revealed mildly elevated leucocytes. After the administration of high-dose intravenous methylprednisolone, her symptoms partially improved. However, MRI T2WI at 16 days after admission showed a lesion with a peripheral hypointense rim in the left side of the cingulate gyrus, which had ring enhancement on contrast CT. FLAIR images at 28 days after admission showed the hyperintense lesion spreading in the subcallosal area and the brainstem, and coronal short inversion time inversion recovery (STIR) images demonstrated bilateral optic neuritis. She was treated with steroid pulse therapy and plasma exchange. Thereafter her symptoms improved. The patient's CSF at 27 days after admission tested positive for anti-myelin oligodendrocyte glycoprotein (anti-MOG) antibodies and anti-N-methyl-D-aspartate (anti-NMDA) receptor antibodies. Encephalitis with optic neuritis in a patient with both anti-MOG and anti-NMDA receptor antibodies is very rare. Coexistence of multiple antibodies in the same patient may contribute to the diversity of autoimmune diseases associated with anti-MOG antibodies or anti-NMDA receptor antibodies.

catena-Poly[[[(2,2'-bipyridine-κ(2)N,N')manganese(II)]-µ-(2,5-dichloro-3,6-dioxocyclo-hexa-1,4-diene-1,4-diolato)-κ(4)O(1),O(6):O(3),O(4)] ethanol disolvate].

The asymmetric unit of the title coordination polymer, {[Mn(C(6)Cl(2)O(4))(C(10)H(8)N(2))]·2C(2)H(5)OH}(n), consists of one Mn(II) ion, one 2,2'-bipyridine (bpy) ligand, one chloranilate (CA(2-)) ligand and two ethanol solvent mol-ecules. The Mn(II) ion is octa-hedrally coordinated by two N atoms of one bpy ligand and four O atoms of two chloranilate ions. The chloranilate ion serves as a bridging ligand between the Mn(II) ions, leading to an infinite zigzag chain along [101]. π-π stacking inter-actions [centroid-centroid distance = 4.098 (2) Å] is observed between the pyridine rings of adjacent chains. The ethanol mol-ecules act as accepters as well as donors for O-H⋯O hydrogen bonds, and form a hydrogen-bonded chain along the a axis. The H atoms of the hy-droxy groups of the two independent ethanol mol-ecules are each disordered over two sites with equal occupancies.

Structural and functional differences of SWIRM domain subtypes.

SWIRM is a conserved domain found in several chromatin-associated proteins. Based on their sequences, the SWIRM family members can be classified into three subfamilies, which are represented by Swi3, LSD1, and Ada2. Here we report the SWIRM structure of human MYb-like, Swirm and Mpn domain-containing protein-1 (MYSM1). The MYSM1 SWIRM structure forms a compact HTH-related fold comprising five alpha-helices, which best resembles the Swi3 SWIRM structure, among the known SWIRM structures. The MYSM1 and Swi3 SWIRM structures are more similar to the LSD1 structure than the Ada2alpha structure. The SWIRM domains of MYSM1 and LSD1 lacked DNA binding activity, while those of Ada2alpha and the human Swi3 counterpart, SMARCC2, bound DNA. The dissimilarity in the DNA-binding ability of the MYSM1 and SMARCC2 SWIRM domains might be due to a couple of amino acid differences in the last helix. These results indicate that the SWIRM family has indeed diverged into three structural subfamilies (Swi3/MYSM1, LSD1, and Ada2 types), and that the Swi3/MYSM1-type subfamily has further diverged into two functionally distinct groups. We also solved the structure of the SANT domain of MYSM1, and demonstrated that it bound DNA with a similar mode to that of the c-Myb DNA-binding domain.

Stereochemistry of reduction in digeranylgeranylglycerophospholipid reductase involved in the biosynthesis of archaeal membrane lipids from Thermoplasma acidophilum.

The basic core structure of archaeal membrane lipids is 2,3-di-O-phytanylglyceryl phosphate, which is formed by reduction of 2,3-di-O-geranylgeranylglyceryl phosphate. This reaction is the final committed step in the biosynthesis of archaeal membrane lipids and is catalyzed by digeranylgeranylglycerophospholipid reductase (DGGGPL reductase). The putative DGGGPL reductase gene (Ta0516m) of Thermoplasma acidophilum was cloned and expressed. The purified recombinant enzyme appeared to catalyze the formation of 2,3-di-O-phytanylglyceryl phosphate from 2,3-di-O-geranylgeranylglyceryl phosphate, which confirmed that the Ta0516m gene of T. acidophilum encodes DGGGPL reductase. The stereospecificity in reduction of 2,3-di-O-phytylglyceryl phosphate by the recombinant reductase appeared to take place through addition of hydrogen in a syn manner by analyzing the enzyme reaction product by NMR spectroscopy.

Biosynthesis of archaeal membrane lipids: digeranylgeranylglycerophospholipid reductase of the thermoacidophilic archaeon Thermoplasma acidophilum.

The basic core structure of archaeal membrane lipids is 2,3-di-O-phytanyl-sn-glyceryl phosphate (archaetidic acid), which is formed by the reduction of 2,3-di-O-geranylgeranylglyceryl phosphate. The reductase activity for the key enzyme in membrane lipid biosynthesis, 2,3-digeranylgeranylglycerophospholipid reductase, was detected in a cell free extract of the thermoacidophilic archaeon Thermoplasma acidophilum. The reduction activity was found in the membrane fraction, and FAD and NADH were required for the activity. The reductase was purified from a cell free extract by ultracentrifugation and four chromatographic steps. The purified enzyme showed a single band at ca. 45 kDa on SDS-PAGE, and catalyzed the formation of archaetidic acid from 2,3-di-O-geranylgeranylglyceryl phosphate. Furthermore, the enzyme also catalyzed the reduction of 2,3-di-O-geranylgeranylglyceryl phosphate analogues such as 2,3-di-O-phytyl-sn-glyceryl phosphate, 3-O-(2,3-di-O-phytyl-sn-glycero-phospho)-sn-glycerol and 2,3-di-O-phytyl-sn-glycero-phosphoethanolamine. The N-terminal 20 amino acid sequence of the purified enzyme was determined and was found to be identical to the sequence encoded by the Ta0516m gene of the T. acidophilum genome. The present study clearly demonstrates that 2,3-digeranylgeranylglycerophospholipid reductase is a membrane associated protein and that the hydrogenation of each double bond of 2,3-digeranylgeranylglycerophospholipids is catalyzed by a single enzyme.