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Mable BK Robertson AV Dart S Di Berardo C Witham L 《Evolution; international journal of organic evolution》2005,59(7):1437-1448
Mating systems in plants are known to be highly labile traits, with frequent transitions from outcrossing to selfing. The genetic basis for breakdown in self-incompatibility (SI) systems has been studied, but data on variation in selfing rates in species for which the molecular basis of SI is known are rare. This study surveyed such variation in Arabidopsis lyrata (Brassicaceae), which is often considered an obligately outcrossing species, to examine the causes and genetic consequences of changes in its breeding system. Based on controlled self-pollinations in the greenhouse, three populations from the Great Lakes region of North America included a minority of self-compatible (SC) individuals, while two showed larger proportions of SC individuals and all populations contained some individuals capable of setting selfed seeds. Loss of SI was not associated with particular haplotypes at the S-locus (as estimated by alleles amplified at the SRK locus, the gene controlling female specificity) and all populations contained similar numbers of SRK alleles, suggesting that some other genetic factor is responsible for modifying the SI reaction. The loss of SI has resulted in an effective shift in the mating system, as the two populations with a high frequency of SC individuals showed significantly lower microsatellite-based multilocus outcrossing rates and higher inbreeding coefficients than the other populations. Based on microsatellites, observed heterozygosities and genetic diversity were also significantly depressed in these populations. These findings provide the unique opportunity to examine in detail the consequences of mating system changes within a species with a well-characterized SI system. 相似文献
33.
Orchid Fleck Virus Infecting Orchids in Paraguay: First Report and Use of Degenerate Primers for its Detection
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Pedro Luis Ramos‐González Humberto Sarubbi‐Orue Luis Gonzales‐Segnana Camila Chabi‐Jesus Juliana Freitas‐Astúa Eliot Watanabe Kitajima 《Journal of Phytopathology》2016,164(5):342-347
The presence of Orchid fleck virus (OFV) in Paraguay was confirmed in orchid plants collected during a survey carried out in 2013. Leaves displayed ringspot and fleck symptoms, and in infected tissues, non‐enveloped, short, rodlike viral particles were observed. Partial OFV N and L genes were amplified using specific and degenerate primers, respectively; the nucleotide sequences demonstrated high identities (98%) with other OFV isolates. Degenerate primers for the L gene were designed considering conserved regions within all of the available OFV sequences and those from the closely related isolates citrus leprosis virus nuclear type (CiLV‐N) and citrus necrotic spot virus. Degenerate primers were also successfully used for the detection of CiLV‐N from infected citrus samples. 相似文献
34.
Donald J. Sarubbi Ramaswamy Narayanan Nitin T. Telang Michael J. Newman 《In vitro cellular & developmental biology. Plant》1990,26(12):1195-1201
Summary Novel or modified serum-free media were developed for the anchorage-dependent growth of nontransformed murine mammary epithelial
cells (MMEC) and Balb/MK murine keratinocytes respectively. Growth rates for both cell lines were similar in serum-containing
and serum-free media. The serum-free media were used to evaluate potential mechanisms of epithelial cell growth regulation
by type 1 transforming growth factor β(TGF-β1). The growth of MMEC and Balb/ MK cells was reversibly inhibited 40–65% in a
time- and dose-dependent fashion by TGF-β1 under both serum-containing and serum-free conditions. Constitutive over-expression
of a stranfected c-myc oncogene inMMEC did not result in loss of sensitivity to growth inhibition by TGF-β1. In addition, Balb/MK and MMEC growth
inhibition by TGF-β1 was not potentiated by polynsaturated fatty acids or reversed by vitamin E. Expgenous type V collagen
was able to mimic the inhibitory effects of TGF-β1 on the serum-free growth of Balb/MK and MMEC. In contrast, collagen type
I and IV, fibronectin and laminin did not inhibit the growth of these cells. The type V collagen used was not contaminated
with TGF-β, and subsaturating, but not saturating concentrations of type V collagen and TGF-β1 were additive with respect
to Balb/MK and MMEC growth inhibition. These results demonstrate that nontransformed epithelial cell growth inhibition by
TGF-β1 is mediated by mechanisms distinct from those observed with certain carcinoma and melanoma cells. Our results also
suggest the possible involvement of type V collagen in Balb/MK and MMEC growth inhibition by TGF-β1.
This work was supported, in part, by grant #R29 CA 44741 from the National Institutes of Health, Bethesda, MD to NTT. 相似文献
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Protein sequences encoded by the relA and the spoT genes of Escherichia coli are interrelated 总被引:7,自引:0,他引:7
relA and spoT are designations for two unlinked Escherichia coli genes whose products function in the synthesis and degradation of guanosine 3',5'-bispyrophosphate during the stringent regulatory response to amino acid deprivation. The RelA protein catalyzes an ATP:GTP 3'-pyrophosphoryl group transfer reaction, and the SpoT protein has a guanosine 3',5'-bispyrophosphate 3'-pyrophosphohydrolyase activity. Both genes have been sequenced recently; the relA gene produces an 84-kDa protein, and the spoT gene is deduced to encode a 79-kDa protein. We report here that the protein sequences of the relA and spoT genes are extensively interrelated. 相似文献
37.
Iannuzzi L Di Meo GP Perucatti A Eggen A Incarnato D Sarubbi F Cribiu E 《Cytogenetics and cell genetics》2001,94(3-4):202-205
Sixteen male Podolian cattle, two sires and their 14 male offspring, were investigated cytogenetically on the basis of a female-like phenotype found in one of them. Eleven male offspring, including the one with female traits, and one of the two sires were found to carry an abnormal Y chromosome which originated from a pericentric inversion of the proximal half of the Yq arm (Yq11-->q12.2), as demonstrated by both banding and FISH mapping techniques with Y-specific molecular markers. 相似文献
38.
Pellegrino Matías S. Frola Ignacio D. Natanael Berardo Gobelli Dino Nader-Macias María E.F. Bogni Cristina I. 《Probiotics and antimicrobial proteins》2019,11(1):74-84
Probiotics and Antimicrobial Proteins - Bovine mastitis causes economic losses on dairy farms worldwide. Lactic acid bacteria (LAB) in animal health are an alternative tool to avoid antibiotic... 相似文献
39.
Intraventricular administration of arginine vasopressin suppresses prolactin release via a dopaminergic mechanism 总被引:1,自引:0,他引:1
The present study was conducted to determine the effects of intracerebroventricular administration of arginine vasopressin (AVP) on the preovulatory prolactin (PRL) surge. Hourly injections of 1 or 5 micrograms AVP from 1200 to 1700 hr on proestrus prevented increases in plasma PRL levels that afternoon. However, following cessation of AVP treatment, a marked increase in PRL levels occurred between 1830 and 2030 hr. This "rebound" secretion of PRL was greater in rats given 5 micrograms AVP than in rats given the lower dose. The suppression of PRL release by AVP appears to be mediated by dopamine since 5 micrograms AVP failed to inhibit PRL release in animals pretreated with the dopamine antagonist domperidone. Interestingly, under these conditions, AVP increased PRL release compared to levels observed in saline-treated rats. In addition to suppressing PRL release, AVP exerted a dose-dependent inhibition of preovulatory LH release. The results suggest a possible interaction between AVP and dopamine in controlling PRL release which likely takes place within the median eminence. 相似文献
40.
Genetic Mapping of Linked Antibiotic Resistance Loci in Neisseria gonorrhoeae 总被引:22,自引:19,他引:22
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Felix A. Sarubbi Jr. Eleanor Blackman P. Frederick Sparling 《Journal of bacteriology》1974,120(3):1284-1292
Loci for resistance to several antibiotics in laboratory-derived strains of Neisseria gonorrhoeae were mapped by genetic transformation. Genes for high-level resistance to streptomycin (str) and spectinomycin (spc) and for low-level resistance to tetracycline (tet) and chloramphenicol (chl) were linked. Also, a locus for high-level resistance to rifampin (rif) was linked to str and tet. The apparent order was rif... str... tet... chl... spc. Loci for resistance to other antibiotics (penicillin, erythromycin) were transferred independently of each other and were not linked to the cluster around str. Similar linkage relationships were found with str, tet, chl, and spc loci obtained from naturally occurring (clinical) isolates of N. gonorrhoeae. 相似文献