RESUMO
A microsatellite-based high-density linkage map for oil palm (Elaeis guinensis Jacq.) was constructed from a cross between two heterozygous parents, a tenera palm from the La Me population (LM2T) and a dura palm from the Deli population (DA10D). A set of 390 simple sequence repeat (SSR) markers was developed in oil palm from microsatellite-enriched libraries and evaluated for polymorphism along with 21 coconut SSRs. A dense and genome-wide microsatellite framework as well as saturating amplified fragments length polymorphisms (AFLPs) allowed the construction of a linkage map consisting of 255 microsatellites, 688 AFLPs and the locus of the Sh gene, which controls the presence or absence of a shell in the oil palm fruit. An AFLP marker E-Agg/M-CAA132 was mapped at 4.7 cM from the Sh locus. The 944 genetic markers were distributed on 16 linkage groups (LGs) and covered 1,743 cM. Our linkage map is the first in oil palm to have 16 independent linkage groups corresponding to the plant's 16 homologous chromosome pairs. It is also the only high-density linkage map with as many microsatellite markers in an Arecaceae species and represents an important step towards quantitative trait loci analysis and physical mapping in the E. guineensis species.
Assuntos
Arecaceae/genética , Mapeamento Cromossômico , Cromossomos de Plantas , Repetições de Microssatélites , Cruzamento , Primers do DNA , Ligação Genética , Reação em Cadeia da Polimerase , Polimorfismo GenéticoRESUMO
Microsatellite [simple-sequence repeat (SSR)] markers were developed and positioned on the genetic map of tetraploid cotton. Three hundred and ninety-two unique microsatellite sequences, all but two containing a (CA/GT) repeat, were isolated, and the deduced primers were used to screen for polymorphism between the Gossypium hirsutum and G. barbadense parents of the mapping population analyzed in our laboratory. The observed rate of polymorphism was 56%. The 204 polymorphic SSRs revealed 261 segregating bands, which ultimately gave rise to 233 mapped loci. The updated status of our genetic map is now of 1,160 loci and 5,519 cM, with an average distance between two loci of 4.8 cM. The presence of a total of 466 microsatellite loci, with an average distance of 12 cM between two SSR loci, now provides wide coverage of the genome of tetraploid cotton and thus represents a powerful means for the production of a consensus map and for the effective tracking of QTLs.
Assuntos
Mapeamento Cromossômico , Genoma de Planta , Gossypium/genética , Repetições de Microssatélites/genética , Primers do DNA , Biblioteca Gênica , Hibridização Genética , Polimorfismo Genético , Poliploidia , Análise de Sequência de DNARESUMO
Autosomal dominant hereditary spastic paraplegia (AD-HSP) is a genetically heterogeneous neurodegenerative disorder characterized by progressive spasticity of the lower limbs. Among the four loci causing AD-HSP identified so far, the SPG4 locus at chromosome 2p2-1p22 has been shown to account for 40-50% of all AD-HSP families. Using a positional cloning strategy based on obtaining sequence of the entire SPG4 interval, we identified a candidate gene encoding a new member of the AAA protein family, which we named spastin. Sequence analysis of this gene in seven SPG4-linked pedigrees revealed several DNA modifications, including missense, nonsense and splice-site mutations. Both SPG4 and its mouse orthologue were shown to be expressed early and ubiquitously in fetal and adult tissues. The sequence homologies and putative subcellular localization of spastin suggest that this ATPase is involved in the assembly or function of nuclear protein complexes.
Assuntos
Adenosina Trifosfatases/genética , Mutação , Paraplegia Espástica Hereditária/genética , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Clonagem Molecular , Análise Mutacional de DNA , Éxons/genética , Etiquetas de Sequências Expressas , Humanos , Íntrons/genética , Camundongos , Mitocôndrias Musculares/metabolismo , Dados de Sequência Molecular , Fosforilação Oxidativa , RNA Mensageiro/análise , RNA Mensageiro/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Paraplegia Espástica Hereditária/enzimologia , Paraplegia Espástica Hereditária/metabolismo , Paraplegia Espástica Hereditária/patologia , EspastinaRESUMO
The cDNA sequence of genomic segment 5 of bovine rotavirus (RF strain) has been inserted into baculovirus transfer vectors, downstream of the polyhedrin promotor. Recombinant baculoviruses containing gene 5 were selected and the protein was expressed to high yields in Spodoptera frugiperda cells. The recombinant protein was inoculated into rabbits and mice to produce specific hyperimmune antisera. The polyclonal antiserum reacted with a protein in rotavirus-infected MA104 cells and with a protein translated in vitro. This serum was also used to confirm that the gene 5 protein is not a structural protein. Recently, the gene 5 product has been predicted to be a zinc finger protein and reported to contain a highly conserved arrangement of cysteine residues; here, we demonstrate that the recombinant gene 5 protein binds zinc and is an RNA-binding protein as are several other zinc finger proteins.