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31.
S. Tang  J. Ou  D. Sun  Y. Zhang  G. Xu  Y. Zhang 《Animal genetics》2011,42(1):108-112
Transforming growth factor‐beta 2 (encoded by TGFB2) is a growth factor that regulates a plethora of cellular functions. In this study, we sequenced the promoter and full‐length exon region of the chicken TGFB2 and found two mutations (g.‐640C>T and g.‐851_‐790del) within the promoter. The two polymorphisms were genotyped in 1030 pedigreed hens recorded for body weight at 7 (BW7), 9 (BW9), 11 (BW11), 13 (BW13), 17 (BW17) weeks old, egg weight at 36 weeks of age (EW36) and egg numbers from the age at first egg (AFE) to 40 weeks of age (EN40). Despite the fact that no mutations were found to have statistically significant genetic effects on egg production, the association results of growth traits showed that both g.‐640C>T and g.‐851_‐790del had significant effects on body weights and that both genotype g.‐640TT and g.‐851_‐790wt/wt were positive for body weight performance. Therefore, the polymorphisms of TGFB2, especially the g.‐851_‐790del mutation associated with body weight at almost all periods, could be potential useful genetic markers to improve the growth of Beijing You chickens.  相似文献   
32.

Background

Bone cancer pain seriously affects the quality of life of cancer patients. Our previous study found that endogenous formaldehyde was produced by cancer cells metastasized into bone marrows and played an important role in bone cancer pain. However, the mechanism of production of this endogenous formaldehyde by metastatic cancer cells was unknown in bone cancer pain rats. Lysine-specific demethylase 1 (LSD1) is one of the major enzymes catalyzing the production of formaldehyde. The expression of LSD1 and the concentration of formaldehyde were up-regulated in many high-risk tumors.

Objective

This study aimed to investigate whether LSD1 in metastasized MRMT-1 breast cancer cells in bone marrows participated in the production of endogenous formaldehyde in bone cancer pain rats.

Methodology/Principal Findings

Concentration of the endogenous formaldehyde was measured by high performance liquid chromatography (HPLC). Endogenous formaldehyde dramatically increased in cultured MRMT-1 breast cancer cells in vitro, in bone marrows and sera of bone cancer pain rats, in tumor tissues and sera of MRMT-1 subcutaneous vaccination model rats in vivo. Formaldehyde at a concentration as low as the above measured (3 mM) induced pain behaviors in normal rats. The expression of LSD1 which mainly located in nuclei of cancer cells significantly increased in bone marrows of bone cancer pain rats from 14 d to 21 d after inoculation. Furthermore, inhibition of LSD1 decreased the production of formaldehyde in MRMT-1 cells in vitro. Intraperitoneal injection of LSD1 inhibitor pargyline from 3 d to 14 d after inoculation of MRMT-1 cancer cells reduced bone cancer pain behaviors.

Conclusion

Our data in the present study, combing our previous report, suggested that in the endogenous formaldehyde-induced pain in bone cancer pain rats, LSD1 in metastasized cancer cells contributed to the production of the endogenous formaldehyde.  相似文献   
33.
The silkworm Bombyx mori L., representing an important economic insect and one of the best models for studying insect immunity, possesses an efficient and sophisticated innate immune system against invasive microorganisms. The innate immune system basically includes humoural immunity and cellular immunity. The humoural immunity, which functions via molecules including humoural factors, lysozymes, phenoloxidase, hemolin, lectins and, in particular, antimicrobial peptides, plays a central role in eliminating the invading pathogens. The cellular immunity is primarily carried out and mediated by plasmatocytes and granular cells of haemocytes in the haemolymph, usually followed by melanization. Additionally, apoptosis, a primary viral defence for insects lacking adaptive immunity, comprises an important part of the silkworm immune system. Currently, there is still the lack of a comprehensive and systematic understanding of the molecular mechanisms of silkworm immunity. We review the latest research progress on silkworm immune mechanisms, including phenoloxidase‐dependent melanization and apoptosis, which is conducive to improving our understanding of the silkworm immune mechanism, clarifying the relationship of various immune mechanisms, and also providing a theoretical basis and reference for the future research of insect immunity.  相似文献   
34.
Rad21 and its meiotic counterpart Rec8,the key components of the cohesin complex,are essential for sister chromatid cohesion and chromosome segregation in mitosis and meiosis,respectively.In contrast to yeast and vertebrates,which have only two RAD21/REC8 genes,the rice genome encodes four Rad21/Rec8 proteins.Here,we report on the cloning and characterization of OsRAD21-2 from rice(Oryza sativa L.).Phylogenetic analysis of the full-length amino acids showed that OsRad21-2 was grouped into the plant-specific...  相似文献   
35.
36.
The advances of next-generation sequencing technology have facilitated metagenomics research that attempts to determine directly the whole collection of genetic material within an environmental sample (i.e. the metagenome). Identification of genes directly from short reads has become an important yet challenging problem in annotating metagenomes, since the assembly of metagenomes is often not available. Gene predictors developed for whole genomes (e.g. Glimmer) and recently developed for metagenomic sequences (e.g. MetaGene) show a significant decrease in performance as the sequencing error rates increase, or as reads get shorter. We have developed a novel gene prediction method FragGeneScan, which combines sequencing error models and codon usages in a hidden Markov model to improve the prediction of protein-coding region in short reads. The performance of FragGeneScan was comparable to Glimmer and MetaGene for complete genomes. But for short reads, FragGeneScan consistently outperformed MetaGene (accuracy improved ∼62% for reads of 400 bases with 1% sequencing errors, and ∼18% for short reads of 100 bases that are error free). When applied to metagenomes, FragGeneScan recovered substantially more genes than MetaGene predicted (>90% of the genes identified by homology search), and many novel genes with no homologs in current protein sequence database.  相似文献   
37.
Ding H  Xu Y  Chen Q  Dai H  Tang Y  Wu J  Shi Y 《Biochemistry》2005,44(8):2790-2799
Small ubiquitin-related modifier SUMO-3 is a member of a growing family of ubiquitin-like proteins (Ubls). So far, four isoforms of SUMO have been identified in humans. It is generally known that SUMO modification regulates protein localization and activity. Previous structure and function studies have been mainly focused on SUMO-1. The sequence of SUMO-3 is 46% identical with that of SUMO-1; nevertheless, functional heterogeneity has been found between the two homologues. Here we report the solution structure of SUMO-3 C47S (residues 14-92) featuring the beta-beta-alpha-beta-beta-alpha-beta ubiquitin fold. Structural comparison shows that SUMO-3 C47S resembles ubiquitin more than SUMO-1. On the helix-sheet interface, a strong hydrophobic interaction contributes to formation of the globular and compact fold. A Gly-Gly motif at the C-terminal tail, extending away from the core structure, is accessible to enzymes and substrates. In vivo, SUMO modification proceeds via a multistep pathway, and Ubc9 plays an indispensable role as the SUMO conjugating enzyme (E2) in this process. To develop a better understanding of SUMO-3 conjugation, the Ubc9 binding surface on SUMO-3 C47S has been detected by chemical shift perturbation using NMR spectroscopy. The binding site mainly resides on the hydrophilic side of the beta-sheet. Negatively charged and hydrophobic residues of this region are highly or moderately conserved among SUMO family members. Notably, the negatively charged surface of SUMO-3 C47S is highly complementary in its electrostatic potentials and hydrophobicity to the positively charged surface of Ubc9. This work indicates dissimilarities between SUMO-3 and SUMO-1 in tertiary structure and provides insight into the specific interactions of SUMO-3 with its modifying enzyme.  相似文献   
38.

Background

Recent advances in DNA sequencing techniques resulted in more than forty sequenced plant genomes representing a diverse set of taxa of agricultural, energy, medicinal and ecological importance. However, gene family curation is often only inferred from DNA sequence homology and lacks insights into evolutionary processes contributing to gene family dynamics. In a comparative genomics framework, we integrated multiple lines of evidence provided by gene synteny, sequence homology and protein-based Hidden Markov Modelling to extract homologous super-clusters composed of multi-domain resistance (R)-proteins of the NB-LRR type (for NUCLEOTIDE BINDING/LEUCINE-RICH REPEATS), that are involved in plant innate immunity.

Results

To assess the diversity of R-proteins within and between species, we screened twelve eudicot plant genomes including six major crops and found a total of 2,363 NB-LRR genes. Our curated R-proteins set shows a 50% average for tandem duplicates and a 22% fraction of gene copies retained from ancient polyploidy events (ohnologs). We provide evidence for strong positive selection and show significant differences in molecular evolution rates (Ka/Ks-ratio) among tandem- (mean = 1.59), ohnolog (mean = 1.36) and singleton (mean = 1.22) R-gene duplicates. To foster the process of gene-edited plant breeding, we report species-specific presence/absence of all 140 NB-LRR genes present in the model plant Arabidopsis and describe four distinct clusters of NB-LRR “gatekeeper” loci sharing syntenic orthologs across all analyzed genomes.

Conclusion

By curating a near-complete set of multi-domain R-protein clusters in an eudicot-wide scale, our analysis offers significant insight into evolutionary dynamics underlying diversification of the plant innate immune system. Furthermore, our methods provide a blueprint for future efforts to identify and more rapidly clone functional NB-LRR genes from any plant species.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-966) contains supplementary material, which is available to authorized users.  相似文献   
39.
Glycoprotein O (gO) is conserved among betaherpesviruses, but little is known about the maturation process of gO in human herpesvirus 6 (HHV-6). We found that HHV-6 gO maturation was accompanied by cleavage of its carboxyl terminus and required coexpression of gH and gL, which promoted the export of gO out of the endoplasmic reticulum (ER). Finally, we also found that gO was not required for HHV-6A growth in T cells.  相似文献   
40.
ABSTRACT

Massive expansions of the hexanucleotide in C9orf72 are the primary genetic origins of familial amyotrophic lateral sclerosis (ALS) and frontal temporal dementia (FTD). Current studies have found that this repeat sequence participates in the disease process by producing neurotoxic substances and reducing the level of C9orf72 protein; however, the progress in the functional study of C9orf72 is slow. Recently, a stable complex, consisting of C9orf72, SMCR8, and WDR41, has been implicated in regulating membrane trafficking and macroautophagy. We reported the cryo-electron microscopy (cryo-EM) structure of the C9orf72-SMCR8-WDR41 complex (CSW complex), unveiling that the CSW complex is a dimer of heterotrimers. Intriguingly, in the heterotrimer of the C9orf72-SMCR8-WDR41, C9orf72 interacts with SMCR8 in a manner similar to the FLCN-FNIP2 complex. Nevertheless, WDR41 is connected to the DENN domain of SMCR8 through its N-terminal β-strand and C-terminal helix but does not directly interact with C9orf72. Notably, the C9orf72-SMCR8 complex was demonstrated to act as a GAP for RAB8A and RAB11A in vitro.  相似文献   
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