Replication of cucumber mosaic virus RNA 1 in cis requires functional helicase-like motifs of the 1a protein.
ABSTRACT The cucumber mosaic virus (CMV) encoded 1a protein contains an NTPase/helicase-like domain. To investigate whether various helicase motifs were required for efficient replication and to establish whether CMV RNA 1 could be replicated efficiently in cis, we constructed deletion mutations in helicase motifs I, III and VI and analyzed their effects on CMV RNA replication in tobacco. CMV replication was not detectable for any of the three helicase mutants, indicating that the helicase domain is crucial for efficient CMV replication. Both the wild-type and mutant 1a proteins could be detected at similar levels after transient expression in infiltrated tissues, indicating that the helicase-motif mutations did not affect the stability of the proteins. Co-inoculation tests with various mutant combinations did not result in complementation. In protoplasts derived from CMV RNA 1-transgenic tobacco, which supported replication of CMV RNAs 2 and 3, the RNA 1 helicase mutants were not replicated detectably in trans, but also did not interfere with the replication of the genomic RNAs, indicating that the conserved helicase motifs of the 1a protein are required in cis for the effective accumulation of RNA 1.
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ABSTRACT: A new data fusion application is presented, in the context of a national research project. This project aims to improve the evaluation of indicators or pathologies of in situ concrete structures, combining measurements provided by various non-destructive evaluation techniques. The indicators of interest are: porosity rate, water saturation, modulus of elasticity, compressive strength, chloride content and carbonatization depth. Any non-destructive measurement will tend to provide an estimation of the unknown indicators, with a certain degree of confidence that is a function of its reliability and sensitivity to each of the indicators. When the estimations converge, data fusion improves the final confidence in the estimated values of these indicators. In case of disagreement, conflicts can be managed by specific operators. An adapted solution has been developed, based on the possibility theory and fuzzy sets. Application results are presented for two simultaneous evaluations of two pairs of indicators: water saturation and porosity rate, and water saturation and modulus of elasticity. These results show that the chosen adaptive operator, which is a function of reliability, is appropriate for this type of problem.NDT & E International 01/2011; 44(5):442-448. · 1.74 Impact Factor