مراعاة الفروق الفردية بين المكلَّفين وأثرها في الاجتهاد التنزيلي

The downloading of the legal rulings on the facts and their transfer from abstraction to application needs a deep philosophical look from Mujtahid and Mufti. Among the things that must be taken into account consider individual differences between taxpayers because these differences may require a change in the Shari'a ruling by the change of the person who owns the incident according to its characteristics and conditions, from the clues that it embraces and requires this change. This indicates that individual differences between taxpayers should be taken into account during tinnitus litigation which is seen as a pilgrimage to the origins of the Sharia and its general rules and its effects were manifested and manifested in the methods and methods of fundamentalists and jurists.

Genetic Dissection of Βc1 Gene

The majority of begomoviruses (viruses of the family Geminiviridae that are transmitted by the whitefly (Bemisia tabaci) occurring in the Old World, in contrast to those occurring in the New World, have monopartite genomes and associate with a group of single stranded DNA satellites which are collectively referred to as betasatellites. Using the betasatellite associated with cotton leaf curl disease (CLCuD; a major constraint to cotton production across Pakistan and northwestern India), Cotton leaf curl Multan betasatellite (CLCuMB), as a model the contribution of the satellite to the symptoms of the begomovirus-betasatellite complex was investigated. The objective of the project was to define the role of betasatellites and, specifically, the βC1 gene product of betasatellites in the begomovirus-betasatellite disease complexes. The work set out to confirm the results of studies with other betasatellites that βC1 has silencing suppressor function and determine the relative contribution of the βC1 to symptoms in plants. Genetic dissection would be used in an effort to identify βC1 sequences/motifs important in the activity of the protein. Finally, efforts were to be made to identify possible interactions between βC1 and virus encoded gene products. Overall these studies would further increase our understanding of the function and interactions of betasatellites in virus infections and provide possible targets for future efforts to engineer resistance to betasatellite requiring begomoviruses. Expression of the single gene (βC1) encoded by CLCuMB from a Potato virus X vector in Nicotiana spp. showed this to be capable of inducing all the symptoms typical of CLCuD, including the leaf like enations frequently seen on infected cotton plants. This contrasts with the phenotype induced in plants in which the βC1 gene is expressed from a stably integrated copy under the control of the Cauliflower mosaic virus 35S promoter. These results show that although the βC1 gene is the major symptom (pathogenicity) determinant of the complex and can induce all the typical symptoms, it must be expressed in the correct tissue for bona fide disease symptoms to ensue; this tissue specificity is likely controlled by the helper begomovirus. Deletion analysis of the βC1 gene of CLCuMB, and subsequent expression of the mutant genes from a PVX vector, showed that deletions at the N-terminus are tolerated but that even small deletion at the C-terminus is not tolerated, leading to a loss of the typical symptoms induced. Additionally the CLCuMB βC1 was shown to be a suppressor of RNA silencing, using the well established GFP silencing system, showing it to have a role in overcoming RNA mediated host defenses in plants. Similar analysis of the βC1 deletion mutants showed sequences at the C-terminus to be important in suppression. Surprisingly, a CLCuMB construct with the βC1 gene deleted remained capable of suppressing GFP silencing. This suggests that CLCuMB may encode additional, possibly cryptic, suppressors. Finally, the CLCuMB was adapted as a virus induced gene silencing (VIGS) vector. CLCuMB was modified by deletion of the βC1 gene and the introduction of restriction endonuclease recognition sequences. This deletion mutant was shown to be capable of maintenance by helper begomoviruses but not to induce the severe symptoms in plants typical of the intact CLCuMB. To assess the potential for use of this as a VIGS vector, a partial sequence of phytoene desaturase (PDS) gene was inserted in a reverse orientation with respect to the βC1 promoter. Inoculation of this construct to plants with the helper begomovirus led to the bleaching of plant tissues typical of silencing of the PDS gene. This effect was initially confined to the stems, petioles and tissue close to the veins of leaves, but subsequently spread outwards. This likely reflects the phloem limited nature of monopartite begomoviruses. The potential uses of this vector are discussed. This work reported here showed that, in common with other betasatellites, the βC1 protein of CLCuMB has suppressor of gene silencing activity and thus is involved in overcoming host defenses to establish virus infection in susceptible plants. For the first time, and in contrast to previous studies with other betasatellites, the βC1 of CLCuMB was shown to be able to induce all symptoms of the disease with which it is associated, when expressed from a phloem limited vector. This conclusively demonstrated that CLCuMB βC1 is the major pathogenicity determinant of the CLCuD complex. Finally the study showed for the first time an interaction between βC1 and the virus-encoded C2 protein which tempers βC1 activity. This is an important finding as it may provide future means of engineering resistance, or at least tolerance, to the CLCuD begomovirus-betasatellite complex.