Isolation and characterization of a novel glycogen synthase kinase-3 gene, <Emphasis Type="Italic">GmGSK</Emphasis>, in <Emphasis Type="Italic">Glycine max</Emphasis> L. that enhances abiotic stress tolerance in <Emphasis Type="Italic">Saccharomyces cerevisiae</Emphasis>

A novel glycogen synthase kinase-3 gene, GmGSK, was isolated from Glycine max. It is 1,596 bp in length with one ORF of 410 amino acids. Southern blot analysis revealed that it has at least two copies in the G. max genome. GmGSK, when transiently expressed in Nicotiana tabacum leaves, was localized in both cell membrane and cytoplasm. Northern blot analysis indicated that GmGSK is expressed in all tissues, with highest expression in the root. GmGSK can be induced by various abiotic stresses. When transformed with GmGSK, Saccharomyces cerevisiae exhibited enhanced resistance to salt and drought stress.     

Characterisation and expression of a novel holotype crystal protein gene, <Emphasis Type="Italic">cry56Aa1</Emphasis>, from <Emphasis Type="Italic">Bacillus</Emphasis> <Emphasis Type="Italic">thuringiensis</Emphasis> strain Ywc2-8

Bacillus thuringiensis isolate Ywc2-8, from soil in Sichuan Basin in western China, contains a spherical crystal harbouring two insecticidal crystal proteins with masses of 70 kDa and 130 kDa. A novel cry-type gene, encoding a 664 amino acid protein with 34% homology to cry29Aa1, was found and cloned from this strain. This gene belongs to a novel holotype cry and is designated as cry56Aa1. It was expressed in E. coli. Insecticidal activity assays showed that recombinant Cry56Aa1 was toxic to both Dipteran (Aedes aegypti) and Lepidopteran (Plutella xylostella and Helicoverpa armigera) pests. Cloning of this gene may help to overcome the increasing resistance of pests to currently used insecticides.     

The Prediction of Nasopharyngeal Carcinoma Mortality Based on Soil Element Levels in China

The relationship between the mortality of nasopharyngeal carcinoma (NPC) and soil trace elements of 29 regions of China was investigated. A total of 29 elements (i.e., Mn, Na, K, Mg, Ca, Sr, Ba, Hg, Pb, Se, In, Yb, Lu, Th, U, Sn, Ti, Zr, Hf, Bi, Ta, Te, Br, I, As, Cr, Cu, Fe, and Zn) were considered. A hybrid strategy called genetic algorithm-partial least squares was used to screen out important elements. As a result, only six elements, i.e., Mn, Ti, Mg, K, Na, and I, were picked out, based on which, a PLS model containing two latent variables exhibited the best performance. According to whether the mortality is larger than 2/100,000 (2?×?10^?5), all the 29 regions were divided into the low-mortality group with 23 regions and the high-mortality group with six regions. Based on the optimal PLS model, all high-mortality regions were successfully classified while only two low-mortality regions were misclassified, i.e., an accuracy of 93%, implying that the selected six elements are effective and successful for predicting the NPC mortality of a region.     

SOX2 modulates alternative splicing in transitional cell carcinoma

Aberrant alternative splicing of key cellular regulators may play a pivotal role in cancer development. To investigate the potential influence of altered alternative splicing on the development of transitional cell carcinoma (TCC), splicing activity in the TCC cell lines TSGH8301 and BFTC905 was examined using the SV40-immortalized uroepithelial cell line SV-HUC-1 as a reference. Our results indicate a significant alteration in splice site selection in the TCC cell lines. By gene expression profiling and subsequent validation, we discovered that sex-determining region Y-box protein 2 (SOX2) is specifically upregulated in BFTC905. Furthermore, ectopic expression of SOX2 modulates alternative splicing of the splicing reporter in vivo. More significantly, using an in vitro pull-down assay, it was found that SOX2 exhibits RNA-binding capability. Our observations suggest that SOX2 modulates alternative splicing by functioning as a splicing factor.     

Rapamycin promotes β-amyloid production via ADAM-10 inhibition

Rapamycin is a well known immunosuppressant drug for rejection prevention in organ transplantation. Numerous clinical trials using rapamycin analogs, involving both children and adults with various disorders are currently ongoing worldwide. Most recently, rapamycin gained much attention for what appears to be life-span extending properties when administered to mice. The risk for Alzheimer disease (AD) is strongly and positively correlated with advancing age and is characterized by deposition of β-amyloid peptides (Aβ) as senile plaques in the brain. We report that rapamycin (2.5 μM), significantly increases Aβ generation in murine neuron-like cells (N2a) transfected with the human “Swedish” mutant amyloid precursor protein (APP). In concert with these observations, we found rapamycin significantly decreases the neuroprotective amino-terminal APP (amyloid precursor protein) cleavage product, soluble APP-α (sAPP-α) while increasing production of the β-carboxyl-terminal fragment of APP (β-CTF). These cleavage events are associated with decreased activation of a disintegrin and metallopeptidase domain-10 (ADAM-10), an important candidate α-secretase which opposes Aβ generation. To validate these findings in vivo, we intraperitoneal (i.p.) injected Tg2576 Aβ-overproducing transgenic mice with rapamycin (3 mg/kg/day) for 2 weeks. We found increased Aβ levels associated with decreased sAPP-α at an average rapamycin plasma concentration of 169.7 ± 23.5 ng/mL by high performance liquid chromatography (HPLC). These data suggest that although rapamycin may increase the lifespan in some mouse models, it may not decrease the risk for age-associated neurodegenerative disorders such as AD.     

A homozygous mutation in the tight-junction protein JAM3 causes hemorrhagic destruction of the brain, subependymal calcification, and congenital cataracts

The tight junction, or zonula occludens, is a specialized cell-cell junction that regulates epithelial and endothelial permeability, and it is an essential component of the blood-brain barrier in the cerebrovascular endothelium. In addition to functioning as a diffusion barrier, tight junctions are also involved in signal transduction. In this study, we identified a homozygous mutation in the tight-junction protein gene JAM3 in a large consanguineous family from the United Arab Emirates. Some members of this family had a rare autosomal-recessive syndrome characterized by severe hemorrhagic destruction of the brain, subependymal calcification, and congenital cataracts. Their clinical presentation overlaps with some reported cases of pseudo-TORCH syndrome as well as with cases involving mutations in occludin, another component of the tight-junction complex. However, massive intracranial hemorrhage distinguishes these patients from others. Homozygosity mapping identified the disease locus in this family on chromosome 11q25 with a maximum multipoint LOD score of 6.15. Sequence analysis of genes in the candidate interval uncovered a mutation in the canonical splice-donor site of intron 5 of JAM3. RT-PCR analysis of a patient lymphoblast cell line confirmed abnormal splicing, leading to a frameshift mutation with early termination. JAM3 is known to be present in vascular endothelium, although its roles in cerebral vasculature have not been implicated. Our results suggest that JAM3 is essential for maintaining the integrity of the cerebrovascular endothelium as well as for normal lens development in humans.     

Bcl-2、Fas和FasL在BPH组织中的表达及其意义

目的:研究凋亡相关基因Bcl-2、Fas和FasL在前列腺增生组织中表达,并探讨其与前列腺增生症的关系.方法:收集哈尔滨医科大学附属第二医院2004年5月--2005年8月前列腺增生症(BPH)组织标本36例,前列腺癌(PCa)组织标本12例和正常前列腺(NP)组织标本7例.应用免疫组织化学SABC方法,检测BPH、PCa和NP组织标本中凋亡相关基因Bcl-2、Fas和FasL的表达,并探讨Bcl-2、Fas和FasL的表达与前列腺增生症的关系.结果:①BPH与PCa组Bcl-2蛋白阳性表达明显高于NP组(P<0.05),而BPH组与PCa组阳性表达无显著差异;PCa组Fas表达显著低于BPH和NP(P<0.05、0.01),而BPH和NP组之间差异也有显著性(P<0.05);FasL在三组之间表达差异均无显著性(P>0.05).②在BPH组织中Bcl-2的表达与Fas表达呈负相关(P(0.05),与FasL表达呈正相关(P<0.05),余均未见相关性.结论:Bcl-2、Fas、FasL均参与了BPH的发生发展过程,Bcl-2、Fas、FasL表达的综合结果可能是引起BPH的原因之一.     

The Post-meiotic Deficicent Anther1 （PDA1） gene is required for post-meiotic anther development in rice

To understand the molecular mechanism of male reproductive development in the model crop rice,we isolated a complete male sterile mutant post-meiotic deficient anther1 (pda1) from a γ-ray-treated rice mutant library.Genetic analysis revealed that the pda1 mutant was controlled by a recessive nucleus gene.The pda1 mutant anther seemed smaller with white appearance.Histological analysis demonstrated that the pda1 mutant anther undergoes normal early tapetum development without obvious altered meiosis.However,the pda1 mutant displayed obvious defects in postmeiotic tapetal development,abnormal degeneration occurred in the tapetal cells at stage 9 of anther development.Also we observed abnormal lipidic Ubisch bodies from the tapetal layer of the pda1 mutant,causing no obvious pollen exine formation.RT-PCR analysis indicated that the expression of genes involved in anther development including GAMYB,OsC4 and Wax-deficient anther1 (WDA1) was greatly reduced in the pda1 mutant anther.Using map-based cloning approach,the PDA1 gene was finely mapped between two markers HLF610 and HLF627 on chromosome 6 using 3,883 individuals of F2 population.The physical distance between HLF610 and HLF627 was about 194 kb.This work suggests that PDA1 is required for post-meiotic tapetal development and pollen/microspore formation in rice.