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21.
Polygalacturonase inhibiting protein (PGIP) is localized in plant cell walls and plays an important role both in pectic substance metabolism and in prevention of the penetration of phytopathogenic microorganisms. Apparently, PGIP is responsible for the specificity of cell--cell interactions during pollination or inoculation by fungi nonpathogenic for the particular plant. PGIPs from different plants share a basic common structure. They are rather thermostable glycoproteins enriched with leucine and contain about 20% carbohydrates; the molecular weight varies between 37-54 kD. The synthesis of PGIP is encoded by one gene, and its expression is stimulated by injury and fungal infection. The resistance of plant tissues to infection frequently correlates with PGIP expression and with inhibiting action on fungal PG. Thus, PGIP is believed to be useful for gene engineering to obtain transgenic plants resistant to fungal infection or retaining commercial value during storage. 相似文献
22.
First-egg date fluctuations for the Pied Flycatcher Ficedula hypoleuca in the woodlands of mid-Wales in the twentieth century 总被引:1,自引:1,他引:0
EM. SLATER 《Ibis》1999,141(3):497-499
23.
Loss of p14ARF in tumor cells facilitates replication of the adenovirus mutant dl1520 (ONYX-015) 总被引:14,自引:0,他引:14
Ries SJ Brandts CH Chung AS Biederer CH Hann BC Lipner EM McCormick F Korn WM 《Nature medicine》2000,6(10):1128-1133
The adenovirus mutant dl1520 (ONYX-015) does not express the E1B-55K protein that binds and inactivates p53. This virus replicates in tumor cells with mutant p53, but not in normal cells with functional p53. Although intra-tumoral injection of dl1520 shows promising responses in patients with solid tumors, previous in vitro studies have not established a close correlation between p53 status and dl1520 replication. Here we identify loss of p14ARF as a mechanism that allows dl1520 replication in tumor cells retaining wild-type p53. We demonstrate that the re-introduction of p14ARF into tumor cells with wild-type p53 suppresses replication of dl1520 in a p53-dependent manner. Our study supports the therapeutic use of dl1520 in tumors with lesions within the p53 pathway other than mutation of p53. 相似文献
24.
Antibodies to citrullinated proteins and differences in clinical progression of rheumatoid arthritis
van der Helm-van Mil AH Verpoort KN Breedveld FC Toes RE Huizinga TW 《Arthritis research & therapy》2005,7(5):R949-R958
Antibodies to citrullinated proteins (anti-cyclic-citrullinated peptide [anti-CCP] antibodies) are highly specific for rheumatoid
arthritis (RA) and precede the onset of disease symptoms, indicating a pathogenetic role for these antibodies in RA. We recently
showed that distinct genetic risk factors are associated with either anti-CCP-positive disease or anti-CCP-negative disease.
These data are important as they indicate that distinct pathogenic mechanisms are underlying anti-CCP-positive disease or
anti-CCP-negative disease. Likewise, these observations raise the question of whether anti-CCP-positive RA and anti-CCP-negative
RA are clinically different disease entities. We therefore investigated whether RA patients with anti-CCP antibodies have
a different clinical presentation and disease course compared with patients without these autoantibodies. In a cohort of 454
incident patients with RA, 228 patients were anti-CCP-positive and 226 patients were anti-CCP-negative. The early symptoms,
tender and swollen joint count, and C-reactive protein level at inclusion, as well as the swollen joint count and radiological
destruction during 4 years of follow-up, were compared for the two groups. There were no differences in morning stiffness,
type, location and distribution of early symptoms, patients' rated disease activity and C-reactive protein at inclusion between
RA patients with and without anti-CCP antibodies. The mean tender and swollen joint count for the different joints at inclusion
was similar. At follow-up, patients with anti-CCP antibodies had more swollen joints and more severe radiological destruction.
Nevertheless, the distribution of affected joints, for swelling, bone erosions and joint space narrowing, was similar. In
conclusion, the phenotype of RA patients with or without anti-CCP antibodies is similar with respect to clinical presentation
but differs with respect to disease course. 相似文献
25.
Background
In crossbreeding programs, genomic selection offers the opportunity to make efficient use of information on crossbred (CB) individuals in the selection of purebred (PB) candidates. In such programs, reference populations often contain genotyped PB animals, although the breeding objective is usually more focused on CB performance. The question is what would be the benefit of including a larger proportion of CB individuals in the reference population.Methods
In a deterministic simulation study, we evaluated the benefit of including various proportions of CB animals in a reference population for genomic selection of PB animals in a crossbreeding program. We used a pig breeding scheme with selection for a moderately heritable trait and a size of 6000 for the reference population.Results
Applying genomic selection to improve the performance of CB individuals, with a genetic correlation between PB and CB performance (rPC) of 0.7, selection accuracy of PB candidates increased from 0.49 to 0.52 if the reference population consisted of PB individuals, it increased to 0.55 if the reference population consisted of the same number of CB individuals, and to 0.60 if the size of the CB reference population was twice that of the reference population for each PB line. The advantage of using CB rather than PB individuals increased linearly with the proportion of CB individuals in the reference population. This advantage disappeared quickly if rPC was higher or if the breeding objective put some emphasis on PB performance. The benefit of adding CB individuals to an existing PB reference population was limited for high rPC.Conclusions
Using CB rather than PB individuals in a reference population for genomic selection can provide substantial advantages, but only when correlations between PB and CB performances are not high and PB performance is not part of the breeding objective. 相似文献26.
Joyce JBC van Beers Annemiek Willemze Judith Stammen-Vogelzangs Jan W Drijfhout René EM Toes Ger J M Pruijn 《Arthritis research & therapy》2012,14(1):R35-16
Introduction
Fibronectin is one of the most abundant proteins present in the inflamed joint. Here, we characterized the citrullination of fibronectin in the joints of rheumatoid arthritis (RA) patients and studied the prevalence, epitope specificity and human leukocyte antigen (HLA) association of autoantibodies against citrullinated fibronectin in RA.Methods
Citrullinated residues in fibronectin isolated from RA patient synovial fluid were identified by mass spectrometry. The corresponding citrullinated and non-citrullinated peptides were synthesized and used to analyze the presence of autoantibodies to these peptides in RA sera and sera from other diseases and healthy controls by ELISA. The data were compared with risk factors like shared epitope HLA alleles and smoking, and with clinical features.Results
Five citrullinated residues were identified in fibronectin from RA synovial fluid. RA sera reacted in a citrulline-dependent manner with two out of four citrullinated fibronectin peptides, one of which contains two adjacent citrulline residues, in contrast to non-RA sera, which were not reactive. The most frequently recognized peptide (FN-Cit1035,1036, LTVGLTXXGQPRQY, in which × represents citrulline) was primarily targeted by anti-CCP (cyclic citrullinated peptide) 2-positive RA patients. Anti-FN-Cit1035,1036 autoantibodies were detected in 50% of established anti-CCP2-positive RA patients and in 45% of such patients from a early arthritis clinic. These antibodies appeared to be predominantly of the immunoglobulin G (IgG) isotype and to be associated with HLA shared epitope alleles (odds ratio = 2.11).Conclusions
Fibronectin in the inflamed synovia of RA patients can be citrullinated at least at five positions. Together with the flanking amino acids, three of these citrullinated residues comprise two epitopes recognized by RA autoantibodies. Anti-citrullinated fibronectin peptide antibodies are associated with HLA shared epitope alleles. 相似文献27.
Background
There is a frequent need to obtain sets of functionally equivalent homologous proteins (FEPs) from different species. While it is usually the case that orthology implies functional equivalence, this is not always true; therefore datasets of orthologous proteins are not appropriate. The information relevant to extracting FEPs is contained in databanks such as UniProtKB/Swiss-Prot and a manual analysis of these data allow FEPs to be extracted on a one-off basis. However there has been no resource allowing the easy, automatic extraction of groups of FEPs – for example, all instances of protein C. 相似文献28.
Satou Y Mineta K Ogasawara M Sasakura Y Shoguchi E Ueno K Yamada L Matsumoto J Wasserscheid J Dewar K Wiley GB Macmil SL Roe BA Zeller RW Hastings KE Lemaire P Lindquist E Endo T Hotta K Inaba K 《Genome biology》2008,9(10):R152-11
Background
The draft genome sequence of the ascidian Ciona intestinalis, along with associated gene models, has been a valuable research resource. However, recently accumulated expressed sequence tag (EST)/cDNA data have revealed numerous inconsistencies with the gene models due in part to intrinsic limitations in gene prediction programs and in part to the fragmented nature of the assembly.Results
We have prepared a less-fragmented assembly on the basis of scaffold-joining guided by paired-end EST and bacterial artificial chromosome (BAC) sequences, and BAC chromosomal in situ hybridization data. The new assembly (115.2 Mb) is similar in length to the initial assembly (116.7 Mb) but contains 1,272 (approximately 50%) fewer scaffolds. The largest scaffold in the new assembly incorporates 95 initial-assembly scaffolds. In conjunction with the new assembly, we have prepared a greatly improved global gene model set strictly correlated with the extensive currently available EST data. The total gene number (15,254) is similar to that of the initial set (15,582), but the new set includes 3,330 models at genomic sites where none were present in the initial set, and 1,779 models that represent fusions of multiple previously incomplete models. In approximately half, 5'-ends were precisely mapped using 5'-full-length ESTs, an important refinement even in otherwise unchanged models.Conclusion
Using these new resources, we identify a population of non-canonical (non-GT-AG) introns and also find that approximately 20% of Ciona genes reside in operons and that operons contain a high proportion of single-exon genes. Thus, the present dataset provides an opportunity to analyze the Ciona genome much more precisely than ever. 相似文献29.
30.