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To determine the expression of CXCL12 in human spleens with extramedullary haematopoiesis (EMH) for clarifying the association of splenic haematopoietic stem cells (HSCs) with CXCL12, which has been demonstrated to be a marker of bone marrow niches.

AbstractRecently, the occurrence of chalky grain caused by high temperature stress at the ripening stage has been a global problem for rice. We previously showed that the deep and permanent irrigation method, which is the combination of the V-furrow direct seeding and deep-flood irrigation methods, reduced chalky grain occurrence. To study the possible physiological mechanisms for reduced chalky grain occurrence by the deep and permanent irrigation method, we conducted field experiments in 2008 and 2009 to examine the effects of the deep-flood treatment on plant nitrogen (N) content, stomatal conductance and photosynthetic rate especially at the ripening stage. Results showed that in the deep-flood treatment that maintained a 20 cm water depth, leaf N content was consistently and significantly higher than the control with only a 10 cm water depth. Except two measured days, the stomatal conductance under the deep-flood treatment was significantly higher than in the control. Furthermore, stomatal conductance and photosynthetic rate in the deep-flood treatment were always significantly higher than in the control in both years. Thus, the deep-flood treatment enhanced N uptake, and consequently photosynthetic activity, resulting in the reduction of chalky grain formation, as previously reported. Accordingly, the effects of deep- flood treatment on grain quality improvement in rice may possibly be attributed to the improvement in source activity.

AbstractIn Abashiri in eastern Hokkaido, Japan, grain yields of winter wheat (Triticum aestivumL. cv. Hokushin) in the western area, with umbric andosol or dystric cambisol soil types, are lower and unstable compared to those in the eastern area, with mostly haplic andosol soil type. The aim of this study was to evaluate yield differences between the eastern and western areas. The vertical root distribution of wheat plants was examined over two seasons in farmers’ fields in both areas by a wall profile method. Plants grown in the western area had shallower root systems than those grown in the eastern area. Poor soil porosity and high soil penetration resistance suppressed the vertical distribution of root systems in umbric andosol and dystric cambisol. Grain yields were not always correlated with the amount and distribution of the root system. Grain yield in the 2004/2005 season was not correlated with root depth index, whereas it was positively correlated in the 2005/2006 season. During the period from heading to maturity (mid June to late July) over the two seasons, grain yield was associated with precipitation more than with temperature and total solar radiation. In the 2005/2006 season, during the late growing stage of wheat, precipitation was extremely low and soils were very dry. The difference in grain yield between the eastern and western areas was significant and negatively related to precipitation during the period from heading to maturity. Significant correlations of yield with sunshine duration and solar radiation from the heading stage to maturity were observed only on haplic andosol. The results suggest that the major factor controlling yearly changes in the difference in grain yield of winter wheat between the eastern and western areas is the difference in photosynthetic ability, which is based on rooting depth and water supply in response to solar radiation during the late growing stage.

We identified seven novel variants of streptococcal pyrogenic exotoxin G (SPEGG), a superantigen, in Streptococcus dysgalactiae subsp. dysgalactiae or equisimilis isolates from clinical cases of infection in humans and animals. Phylogenetic analysis of the SPEGG variants indicated two clades in the dendrogram: one composed of variants derived from the bacteria isolated from the humans and the other composed of variants from the bacteria isolated from the animals. Bovine peripheral blood mononuclear cells (PBMCs) were stimulated effectively by recombinant SPEGGs (rSPEGGs) expressed in Escherichia coli, while human PBMCs were not stimulated well by any of the rSPEGGs tested. SPEGGs selectively stimulated bovine T cells bearing V{szligbeta}1,10 and V{szligbeta}4. Bovine serum showed reactivity to the rSPEGG proteins. These results indicated that SPEGGs have properties as superantigens, and it is likely that SPEGGs play a pathogenic role in animals.

ABSTRACTWe identified seven novel variants of streptococcal pyrogenic exotoxin G (SPEGG), a superantigen, in Streptococcus dysgalactiaesubsp. dysgalactiaeor equisimilisisolates from clinical cases of infection in humans and animals. Phylogenetic analysis of the SPEGG variants indicated two clades in the dendrogram: one composed of variants derived from the bacteria isolated from the humans and the other composed of variants from the bacteria isolated from the animals. Bovine peripheral blood mononuclear cells (PBMCs) were stimulated effectively by recombinant SPEGGs (rSPEGGs) expressed in Escherichia coli, while human PBMCs were not stimulated well by any of the rSPEGGs tested. SPEGGs selectively stimulated bovine T cells bearing Vβ1,10 and Vβ4. Bovine serum showed reactivity to the rSPEGG proteins. These results indicated that SPEGGs have properties as superantigens, and it is likely that SPEGGs play a pathogenic role in animals.

It has been shown that simultaneous blockade of CD28- and CD40-mediated costimulatory signals significantly prolongs allograft survival. Although these results led to an expectation of the establishment of specific immunotolerant therapy for organ transplantation, it became evident that these treatments rarely resulted in indefinite allograft survival. To uncover the mechanisms underlying these costimulation blockade-resistant allograft rejections, we studied the process of allogenic skin graft rejection in CD28 and CD40 ligand (L) double-deficient (double-knockout dKO) mice.

Pkd2,the mouse homologue of PKD2,the gene responsible for the second form of autosomal dominant polycystic kidney disease, is highly expressed in fetal and adult mouse tissues. The expression of Pkd2is developmentally regulated. To begin to dissect out the regulatory mechanism of Pkd2expression, we characterized the basic features of the gene structure and identified potential cis-regulatory elements of Pkd2transcription. Pkd2spans 42 kb with a transcription start site 165 bp upstream of the translation start codon. Exon 1 of Pkd2is 755 bp long, and the full-length transcript is 5215 bp. The Pkd2promoter region is GC-rich and lacks a consensus TATA or CCAAT box. Consensus binding sites for the transcription factors Sp-1, NF-1, and Ap-2 lie in the 5′ upstream region of Pkd2.The Sp-1 binding site is conserved in 5′ upstream sequences of both the mouse and the human genes. The CAT activity of a series of upstream segments from +178 to −2749 was assessed in MDCK, LLCPK1, COS-7, and HEK293 cells. Deletion analysis identified a 409-bp fragment from position −221 to +178 responsible for basal promoter activity. A 922-bp fragment from –744 to +178 showed the highest level of CAT activity in the cell lines tested. These data define a functional promoter candidate region for Pkd2.

PKD2, the second gene for the autosomal dominant polycystic kidney disease (ADPKD), encodes a protein, polycystin-2, with predicted structural similarity to cation channel subunits. However, the function of polycystin-2 remains unknown. We used polyclonal antisera specific for the intracellular NH2and COOH termini to identify polycystin-2 as an ∼110-kDa integral membrane glycoprotein. Polycystin-2 from both native tissues and cells in culture is sensitive to Endo H suggesting the continued presence of high-mannose oligosaccharides typical of pre-middle Golgi proteins. Immunofluorescent cell staining of polycystin-2 shows a pattern consistent with localization in the endoplasmic reticulum. This finding is confirmed by co-localization with protein-disulfide isomerase as determined by double indirect immunofluorescence and co-distribution with calnexin in subcellular fractionation studies. Polycystin-2 translation products truncated at or after Gly821retain their exclusive endoplasmic reticulum localization while products truncated at or before Glu787additionally traffic to the plasma membrane. Truncation mutants that traffic to the plasma membrane acquire Endo H resistance and can be biotinylated on the cell surface in intact cells. The 34-amino acid region Glu787-Ser820, containing two putative phosphorylation sites, is responsible for the exclusive endoplasmic reticulum localization of polycystin-2 and is the site of specific interaction with an as yet unidentified protein binding partner for polycystin-2. The localization of full-length polycystin-2 to intracellular membranes raises the possibility that the PKD2 gene product is a subunit of intracellular channel complexes.

ThePKHD1(polycystic kidney and hepatic disease 1) gene responsible for autosomal recessive polycystic kidney disease has been mapped to 6p21.1–p12 to an ∼1-cM interval flanked by the markers D6S1714/D6S243 and D6S1024. We have developed a sequence-ready BAC/PAC-based contig map of this region as the next step for the positional cloning ofPKHD1.This contig comprising 52 clones spanning ∼1 Mb was established by content mapping of 44 BAC/PAC-end-derived STSs, 3 known genetic markers, 5 YAC-end-derived STSs, 3 random STSs, 1 previously mapped gene, and 1 EST. The average depth per marker is 6.3 clones, and the average STS density is 20 kb. The genomic clone overlaps were confirmed by restriction fragment fingerprint analysis. A high-resolution BAC/PAC-based contig map is essential to the ultimate goal of identifying thePKHD1gene.

The gene responsible for the second form of autosomal dominant polycystic kidney disease,PKD2,has recently been identified. We now describe the cloning, genomic localization, cDNA sequence, and expression analysis of its murine homologue,Pkd2.The cloned cDNA sequence is 5134 bp long and is predicted to encode a 966-amino-acid integral membrane protein with six membrane-spanning domains and intracellular NH2and COOH termini. Pkd2 is highly conserved with 91% identity and 98% similarity to polycystin-2 at the amino acid level.Pkd2mRNA is widely expressed in mouse tissues.Pkd2maps to mouse Chromosome 5 and is excluded as a candidate gene for previously mapped mouse mutations resulting in a polycystic kidney phenotype.

Mutations inPKD2cause autosomal dominant kidney disease (ADPKD). Polycystin-2, thePKD2gene product, is an integral membrane glycoprotein of unknown function. We have identifiedPKD2L, another member of thePKD2gene family.PKD2Lis expressed in adult heart and skeletal muscle, brain, spleen, testis, and retina, and alternative transcripts of 2.4, 2.7, and 3.0 kb are seen. PKD2L shows 56% identity and 76% similarity with polycystin-2 over a 581-amino-acid span; however, the COOH-terminal 65 residues of PKD2L are unrelated to PKD2.PKD2Lis localized to chromosome 10q25 and is excluded as a candidate gene for autosomal recessive polycystic kidney disease, autosomal dominant polycystic liver disease, and the third form of ADPKD. Given the high degree of homology between PKD2L and PKD2, it is likely that the respective functions of these proteins are also closely related.

PKD2, the gene defective in the second form of autosomal dominant polycystic kidney disease (ADPKD), has been identified by positional cloning and found to encode an integral membrane protein with similarity to the gene for the more common form of ADPKD and to calcium channels. We have determined the exon–intron structure of the PKD2 gene. PKD2 is encoded in at least 15 exons with the translation start site in exon 1. All the splice acceptor and donor sites conform to the AG/GT rule. We have designed a series of intronic oligonucleotide primers for amplifying the entire coding sequence from genomic DNA in segments well suited to mutation analysis using conventional screening strategies such as SSCA or heteroduplex analysis.

Autosomal recessive polycystic kidney disease is one of the most common hereditary renal cystic diseases in children. Genetic studies have recently assigned the only known locus for this disorder, PKHD1, to chromosome 6p21–p12. We have generated a YAC contig that spans ∼5 cM of this region, defined by the markers D6S1253–D6S295, and have mapped 43 sequence-tagged sites (STS) within this interval. This set includes 20 novel STSs, which define 12 unique positions in the region, and three ESTs. A minimal set of two YACs spans the segment D6S465–D6S466, which contains PKHD1, and estimates of their sizes based on information in public databases suggest that the size of the critical region is <3.1 Mb. Twenty-eight STSs map to this interval, giving an average STS density of <1/150 kb. These resources will be useful for establishing a complete trancription map of the PKHD1 region.

Abstract: Autosomal dominant polycystic kidney disease (ADPKD) is one of the most frequent inherited disorders. The majority of cases are due to mutation of the PKD1 gene, on 16p13.3, while in most of the remainder the disease maps to the PKD2 locus, at chromosome 4q21-q23. Recently, the PKD2 gene has been positionally cloned and three nonsense mutations within the coding sequence of the gene identified. Here we report a systematic mutation screening of all 15 exons of the PKD2 gene in chromosome 4-linked ADPKD families, using heteroduplex and SSCP analyses. We have identified and characterized seven novel mutations, with a detection rate of approximately 90% in the population studied. All of the mutations result in the premature stop of translation: four nonsense changes and three deletions. The deletions are all frameshifting, of four T nucleotides in one case and one G nucleotide in the other two. All mutations are unique and are distributed throughout the gene without evidence of clustering. Comparison of specific mutations with the clinical profile in ADPKD2 families shows no clear correlation.

Mycoplasma bovisis a destructive pathogen that causes large economic losses in rearing cattle for beef and dairy worldwide. M. boviscauses suppression of and evades the host immune response; however, the mechanisms of host immune function involved in M. bovismastitis have not been elucidated. The purpose of this study was to elucidate the characteristics of the bovine immune response to mycoplasmal mastitis. We evaluated the responsiveness of the bovine mammary gland following infusion of M. bovis.