Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPβ-dependent pathway

The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8 on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells. The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPβ binding site was responsible for PRL-induced activation of the MFG-E8 promoter. C/EBPβ activity was found to be up-regulated in PRL-treated cells as revealed by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages, while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter.     

Measuring the number of co-dominants in ecological communities

We suggest a concept that allows the objective determination of the number of co-dominants in a community. We define co-dominants as a subset of species that are more abundant and more uniformly distributed than other species in a given sample. We compare the sample with a model community and use Simpsons diversity index to estimate the apparent number of co-dominants. Dominant species determined in this way are responsible for 70–90% of the total measure of abundance in the sample. The statistical significance of the apparent number of co-dominants may be assessed by a randomization test.     

Treatment with an adenoviral vector encoding hepatocyte growth factor mitigates established cardiac dysfunction in doxorubicin-induced cardiomyopathy

Hepatocyte growth factor (HGF) reportedly exerts beneficial effects on the heart following myocardial infarction and during nonischemic cardiomyopathy, but the precise mechanisms underlying the latter have not been well elucidated. We generated nonischemic cardiomyopathy in mice by injecting them with doxorubicin (15 mg/kg ip). Two weeks later, when cardiac dysfunction was apparent, an adenoviral vector encoding human HGF gene (Ad.CAG-HGF, 1x10(11) particles/mouse) was injected into the hindlimb muscles; LacZ gene served as the control. Left ventricular dilatation and dysfunction normally seen 4 wk after doxorubicin administration were significantly mitigated in HGF-treated mice, as were the associated cardiomyocyte atrophy/degeneration and myocardial fibrosis. Myocardial expression of GATA-4 and a sarcomeric protein, myosin heavy chain, was downregulated by doxorubicin, but the expression of both was restored by HGF treatment. The protective effect of HGF against doxorubicin-induced cardiomyocyte atrophy was confirmed in an in vitro experiment, which also showed that neither cardiomyocyte apoptosis nor proliferation plays significant roles in the present model. Upregulation of c-Met/HGF receptor was noted in HGF-treated hearts. Among the mediators downstream of c-Met, the activation of extracellular signal-regulated kinase (ERK) was reduced by doxorubicin, but the activity was restored by HGF. Levels of transforming growth factor-beta1 and cyclooxygenase-2 did not differ between the groups. Our findings suggest the HGF gene delivery exerts therapeutic antiatrophic/degenerative and antifibrotic effects on myocardium in cases of established cardiac dysfunction caused by doxorubicin. These beneficial effects appear to be related to HGF-induced ERK activation and upregulation of c-Met, GATA-4, and sarcomeric proteins.     

Structural Basis for the Dual Substrate Specificity of DOCK7 Guanine Nucleotide Exchange Factor

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Complex Patterns of Chromosome 11 Aberrations in Myeloid Malignancies Target CBL,MLL, DDB1 and LMO2

Exome sequencing of primary tumors identifies complex somatic mutation patterns. Assignment of relevance of individual somatic mutations is difficult and poses the next challenge for interpretation of next generation sequencing data. Here we present an approach how exome sequencing in combination with SNP microarray data may identify targets of chromosomal aberrations in myeloid malignancies. The rationale of this approach is that hotspots of chromosomal aberrations might also harbor point mutations in the target genes of deletions, gains or uniparental disomies (UPDs). Chromosome 11 is a frequent target of lesions in myeloid malignancies. Therefore, we studied chromosome 11 in a total of 813 samples from 773 individual patients with different myeloid malignancies by SNP microarrays and complemented the data with exome sequencing in selected cases exhibiting chromosome 11 defects. We found gains, losses and UPDs of chromosome 11 in 52 of the 813 samples (6.4%). Chromosome 11q UPDs frequently associated with mutations of CBL. In one patient the 11qUPD amplified somatic mutations in both CBL and the DNA repair gene DDB1. A duplication within MLL exon 3 was detected in another patient with 11qUPD. We identified several common deleted regions (CDR) on chromosome 11. One of the CDRs associated with de novo acute myeloid leukemia (P=0.013). One patient with a deletion at the LMO2 locus harbored an additional point mutation on the other allele indicating that LMO2 might be a tumor suppressor frequently targeted by 11p deletions. Our chromosome-centered analysis indicates that chromosome 11 contains a number of tumor suppressor genes and that the role of this chromosome in myeloid malignancies is more complex than previously recognized.     

Landscape genetic structure of <Emphasis Type="Italic">Betula maximowicziana</Emphasis> in the Chichibu mountain range,central Japan

We evaluated the genetic structure of 16 Betula maximowicziana populations in the Chichibu mountain range, central Japan, located within a 25-km radius; all but two populations were at altitudes of 1,100–1,400 m. The results indicate the effects of geographic topology on the landscape genetic structure of the populations and should facilitate the development of local-scale strategies to conserve and manage them. Analyses involving 11 nuclear simple sequence repeat loci showed that most populations had similar intrapopulation genetic diversity parameters. Population differentiation (F _ST = 0.021, G′_ST = 0.033) parameters for the populations examined were low but were relatively high compared to those obtained in a previous study covering populations in a much larger area with a radius of approximately 1,000 km (F _ST = 0.062, G′_ST = 0.102). Three populations (Iriyama, Kanayamasawa, and Nishizawa) were differentiated from the other populations by Monmonier’s and spatial analysis of molecular variance algorithms or by STRUCTURE analysis. Since a high mountain ridge (nearly 2,000 m) separates the Kanayamasawa and Nishizawa populations from the other 14 populations and the Kanayamasawa and Nishizawa populations are themselves separated by another mountain ridge, the genetic structure appears to be partly due to mountain ridges acting as genetic barriers and restricting gene flow. However, the Iriyama population is genetically different but not separated by any clear geographic barrier. These results show that the landscape genetic structure is complex in the mountain range and we need to pay attention, within landscape genetic studies and conservation programs, to geographic barriers and local population differentiation.     

On the similar spatial arrangement of active site residues in PAPS-dependent and phenolic sulfate-utilizing sulfotransferases

Mammalian sulfotransferases (STs) utilize exclusively the sulfuryl group donor 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to catalyze the sulfurylation reactions based on a sequential transfer mechanism. In contrast, the commensal intestinal bacterial arylsulfate sulfotransferases (ASSTs) do not use PAPS as the sulfuryl group donor, but instead catalyze sulfuryl transfer from phenolic sulfate to a phenol via a Ping-Pong mechanism. Interestingly, structural comparison revealed a similar spatial arrangement of the active site residues as well as the cognate substrates in mouse ST (mSULT1D1) and Escherichia coli CFT073 ASST, despite that their overall structures bear no discernible relationship. These observations suggest that the active sites of PAPS-dependent SULT1D1 and phenolic sulfate-utilizing ASST represent an example of convergent evolution.     

The use of the polymerase chain reaction and restriction fragment length polymorphism technique associated with the classical morphology for characterization of Lymnaea columella, L. viatrix, and L. diaphana (Mollusca: Lymnaeidae)

The specific identification of Lymnaeid snails is based on a comparison of morphological characters of the shell, radula, renal and reproductive organs. However, the identification is complicated by dissection process, intra and interspecific similarity and variability of morphological characters. In the present study, polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) techniques targeted to the first and second internal transcribed spacers (ITS1 and ITS2) rDNA and to the mitochondrial 16S ribosomal gene (16S rDNAmt) were used to differentiate the species Lymnaea columella, L. viatrix, and L. diaphana from some localities of Brazil, Argentina, and Uruguay as well as to verify whether the molecular results corroborates the classical morphological method.PCR-RFLP analysis of the ITS1, ITS2, and 16S using 12 restriction enzymes revealed characteristic patterns for L. columella and L. diaphana which were concordant with the classical morphology. On the other hand, for L. viatrix populations a number of 1 to 6 profiles were generated while morphology provided the species pattern results.     

Crystal structures of the S6K1 kinase domain in complexes with inhibitors

Ribosomal protein S6 kinase 1 (S6K1) is a serine/threonine protein kinase that plays an important role in the PIK3/mTOR signaling pathway, and is implicated in diseases including diabetes, obesity, and cancer. The crystal structures of the S6K1 kinase domain in complexes with staurosporine and the S6K1-specific inhibitor PF-4708671 have been reported. In the present study, five compounds (F108, F109, F176, F177, and F179) were newly identified by in silico screening of a chemical library and kinase assay. The crystal structures of the five inhibitors in complexes with the S6K1 kinase domain were determined at resolutions between 1.85 and 2.10 Å. All of the inhibitors bound to the ATP binding site, lying along the P-loop, while the activation loop stayed in the inactive form. Compound F179, with a carbonyl group in the middle of the molecule, altered the αC helix conformation by interacting with the invariant Lys123. Compounds F176 and F177 bound slightly distant from the hinge region, and their sulfoamide groups formed polar interactions with the protein. The structural features required for the specific binding of inhibitors are discussed.     

Yezonia,a new section ofAraucaria (Araucariaceae) based on permineralized vegetative and reproductive organs ofA. vulgaris comb. nov. from the upper cretaceous of Hokkaido,Japan

A new specimen of an araucarian cone,Araucaria nihongii, was found attached to the vegetative organs ofYezonia vulgaris, and is described asAraucaria vulgaris comb. nov. Thick branches show characteristic bark structure with lenticular patches. Secondary wood is usually araucarioid. Leaves are arranged helically on shoots, which are imbricate, appressed and fused to surface of the stem. External and anatomical features of leaves closely resembleBrachyphyllum. The seed cone is spherical with winged bracts and thin ovuliferous scales. One seed is borne per cone-scale complex. The seed coat and nucellus wall show typical araucarian structure. An araucarian plant that boreBrachyphyllum-like foliage and aEutacta-like seed cone was predicted by Harris in 1979. This reconstructed plant,Araucaria vulgaris, supports this theory and proves the presence of an extinct characteristic-form of the genus. A new section of the genus was proposed forAraucaria vulgaris. Structure and Affinities of the Petrified Plants from the Cretaceous of Northern Japan and Saghalien XV, Consecutive number from previous paper (Nishidaet al. 1993).