Discovery and identification of anti-U1-A snRNP antibody in lung cancer

There are multiple reports of autoimmune response in patients with lung cancer. To investigate whether a novel autoantibody is present in patients with lung cancer and evaluate its clinical diagnostic and prognostic value, sera from 10 patients with lung cancer and 10 normal individuals were analyzed using immunofluorescence and Western blotting. It was found that one serum sample from the patients with squamous carcinoma gave a fine speckled pattern staining in nucleus and had a high titer antinuclear autoantibody which could recognize 31 kD of nuclear protein isolated from both cancer cells and normal cells. The same patient’s serum was further used to immunoprecipitate the target antigen. The protein bands were excised from the SDS-PAGE gels and were analyzed with a Qstar Pulser I Quadrupole time-flight mass spectrometer, and the 31 kD target antigen was identified as U1-AsnRNP. To test the prevalence of anti-U1-AsnRNP antibody, sera from 93 patients including 36 squmaous carcinomas (SCC), 26 adenocarcinomas (Ad), and 31 small cell carcinomas (SCLC) were screened by Western blotting. The results demonstrated that anti-U1-A snRNP antibody was present in 50% of SCC sera, 26.9% of Ad sera and 54.8% of SCLC sera. In this paper, we report for the first time that anti-U1-AsnRNP antibody could be detected in the patients with lung cancer.     

Effects of caffeine on phosphatidylinositide turnover and calcium mobilization in human neuroblastoma SK-N-SH cells

The effects of caffeine on receptor-controlled Ca2+ mobilization and turnover of inositol phosphates in human neuroblastoma SK-N-SH cells were studied. Caffeine inhibited both the rise in cytosolic Ca2+ concentration ([Ca2+]i) evoked by muscarinic receptor agonists and the total production of inositol phosphates in a dose-dependent manner, but to different extents. At 10 mM, caffeine inhibited agonist-evoked generation of inositol phosphates almost completely, whereas the agonist-evoked [Ca2+]i rise remained observable after caffeine treatment, in the absence or presence of extracellular Ca2+. Raising the cytosolic cAMP concentration increased the carbachol-induced [Ca2+]i rise, and this effect was abolished in the presence of caffeine. Our data suggested that caffeine may exert two effects on receptor-controlled Ca2+ mobilization: 1) inhibition of inositol phosphate production, 2) augmentation of the size of the releasable Ca2+ pool by elevating cytosolic cAMP concentration.     

Mutations in the exon 10 of prolactin receptor gene change the egg production performance in Wanjiang white goose

To select the molecular genetic markers related to egg performance of Wanjiang white goose, prolactin receptor gene (PRLR) was adopted to be a candidate gene in our study. Five pairs of primers (P1–P5) were designed to detect the SNPs of PRLR gene by PCR-SSCP method. The results revealed that polymorphisms were discovered in the PCR products amplified with P4 primers in PRLR exon 10, three genotypes were found: AA, AB and AC. The sequence of AB genotype is the same as original sequence (DQ660982) in NCBI. There are five mutations in AA genotype: C → A at 840 bp, C → T at 862 bp, T → C at 875 bp, T → A at 963 bp, A → T at 989 bp, resulting in amino acid mutations: His → Asn, Thr → Ile, Asn → Lys, Thr → Ser, and synonymous mutation at 875 bp. Sequencing revealed five mutations in AC genotype: G → T at 816 bp, A → T at 861 bp, C → T at 862 bp, T → C at 875 bp, A → G at 948 bp, causing amino acid mutations of Val → Phe, Thr → Phe, synonymous mutations at 875 and 963 bp. Besides, there are an N-glycosylation site (NQSR), three casein kinase II phosphorylation sites including SIIE, SKTE, and SLMD in AA genotype; three casein kinase II phosphorylation sites including SIIE, SKTE, and TLMD in AB genotype; three casein kinase II phosphorylation sites including SIFE, SKTE, and TLMD in AC genotype. The annual egg yielding of AB genotype geese are significantly more than those of AA and AC genotype geese on the average (P < 0.05). It is suggested for the first time that PRLR is a promising candidate gene that can affect egg performance in Wanjiang white goose.     

Avian pluripotent stem cells

Pluripotent embryonic stem cells are undifferentiated cells capable of proliferation and self-renewal and have the capacity to differentiate into all somatic cell types and the germ line. They provide an in vitro model of early embryonic differentiation and are a useful means for targeted manipulation of the genome. Pluripotent stem cells in the chick have been derived from stage X blastoderms and 5.5 day gonadal primordial germ cells (PGCs). Blastoderm-derived embryonic stem cells (ESCs) have the capacity for in vitro differentiation into embryoid bodies and derivatives of the three primary germ layers. When grafted onto the chorioallantoic membrane, the ESCs formed a variety of differentiated cell types and attempted to organize into complex structures. In addition, when injected into the unincubated stage X blastoderm, the ESCs can be found in numerous somatic tissues and the germ line. The potential give rise to somatic and germ line chimeras is highly dependent upon the culture conditions and decreases with passage. Likewise, PGC-derived embryonic germ cells (EGCs) can give rise to simple embryoid bodies and can undergo some differentiation in vitro. Interestingly, chicken EG cells contribute to somatic lineages when injected into the stage X blastoderm, but only germ line chimeras have resulted from EGCs injected into the vasculature of the stage 16 embryo. To date, no lines of transgenic chickens have been generated using ESCs or EGCs. Nevertheless, progress towards the culture of avian pluripotent stem cells has been significant. In the future, the answers to fundamental questions regarding segregation of the avian germ line and the molecular basis of pluripotency should foster the full use of avian pluripotent stem cells.     

Acquired Antibody Responses against Plasmodium vivax Infection Vary with Host Genotype for Duffy Antigen Receptor for Chemokines (DARC)

Background

Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC) is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are ‘resistant’ to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens.

Methodology/Findings

We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1) and Duffy binding protein (PvDBP) varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull) were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B). The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion.

Conclusion/Significance

Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the primary mechanisms by which P. vivax evades host immunity is through DARC indirectly down-regulating humoral responses against erythrocytic invasion and development.     

Identification and validation of quantitative trait loci conferring tan spot resistance in the bread wheat variety Ernie

Tan spot, caused by Pyrenophora tritici-repentis, is a foliar disease of wheat, and it can inflict serious reduction in grain yield and quality. The bread wheat variety Ernie was found to be immune to this disease in Australia, and its genetic control was investigated by quantitative trait loci (QTL) analysis using a doubled haploid population. Eight QTL were identified in this population from three independent trials, and four of them were derived from the parent Ernie. The most significant QTL was located on chromosome arm 2BS, explaining 38.2, 29.8 and 36.2% of the phenotypic variance, respectively, in these trials. The effects of the 2BS QTL were further validated in four additional populations. The presence of this single QTL reduced disease severity by between 29.2 and 67.1% with an average of 50.5%. The significant effects of this QTL and its consistent detection across all the trials with different genetic backgrounds make it an ideal target for breeding programmes as well as for its further characterization. Data from this study also showed that neither plant height nor heading date significantly affects tan spot resistance.     

Interaction between the nucleotide exchange factor Mge1 and the mitochondrial Hsp70 Ssc1

Function of Hsp70s such as DnaK of the Escherichia coli cytoplasm and Ssc1 of the mitochondrial matrix of Saccharomyces cerevisiae requires the nucleotide release factors, GrpE and Mge1, respectively. A loop, which protrudes from domain IA of the DnaK ATPase domain, is one of six sites of interaction revealed in the GrpE:DnaK co-crystal structure and has been implicated as a functionally important site in both DnaK and Ssc1. Alanine substitutions for the amino acids (Lys-108 and Arg-213 of Mge1) predicted to interact with the Hsp70 loop were analyzed. Mge1 having both substitutions was able to support growth in the absence of the essential wild-type protein. K108A/R213A Mge1 was able to stimulate nucleotide release from Ssc1 and function in refolding of denatured luciferase, albeit higher concentrations of mutant protein than wild-type protein were required. In vitro and in vivo assays using K108A/R213A Mge1 and Ssc1 indicated that the disruption of contact at this site destabilized the interaction between the two proteins. We propose that the direct interaction between the loop of Ssc1 and Mge1 is not required to effect nucleotide release but plays a role in stabilization of the Mge1-Ssc1 interaction. The robust growth of the K108A/R213A MGE1 mutant suggests that the interaction between Mge1 and Ssc1 is tighter than required for function in vivo.