RESUMO
A novel y-type high molecular mass glutenin subunit (HMM-GS) possessing a mobility that is slightly slower than that of the subunit Dy10 obtained by SDS-PAGE, named Dy10.1t, in the wild wheat Aegilops tauschii was identified by 1- and 2-dimensional gel electrophoresis, capillary electrophoresis, and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS). The gene encoding the HMM subunit Dy10.1t was amplified with allele-specific PCR primers, and the amplified products were cloned and sequenced. The coding domain of the Dy10.1t subunit gene consisted of 1980 bp encoding a protein of 658 residues with an M rs of 68 611 Da, which was similar to the M rs determined by MALDI-TOF-MS. The deduced amino acid sequence indicated that Dy10.1t subunit displayed a greater similarity to the Dy12 subunit, differing by only 8 amino acid substitutions. Six coding region single-nucleotide polymorphisms were discovered in the Dy10.1t gene by multiple alignments (1 per 330 bp), 1 in the N-terminal domain and the others in the central repeats. Five of them resulted in residue substitutions, whereas 3 created enzyme site changes. The homology and neighbour-joining trees constructed from code domain sequences of 20 x- and y-type glutenin genes from different Triticum species separated into 2 halves, which corresponded to the x-type and y-type HMM glutenin alleles. Phylogenetic analysis revealed that the Glu-1 gene duplication event probably occurred at about 16.83 million years ago, whereas the divergence times of A, B, and D genomes within x-type and y-type halves were before 7.047 and 10.54 million years ago, respectively.
Assuntos
DNA de Plantas/genética , Glutens/genética , Triticum/genética , Alelos , Sequência de Aminoácidos , Clonagem Molecular , DNA de Plantas/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Técnicas Genéticas , Glutens/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Subunidades Proteicas/genética , Subunidades Proteicas/isolamento & purificação , Alinhamento de Sequência , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Plant and animal genomes contain an abundance of small genes that produce RNAs of about 22 nucleotides in length, which was dubbed as microRNAs. These newly found endogenous RNAs may participate in a wide range of genetic regulatory pathways and play an important role in the development. This paper is focused on the finding of the microRNAs, its mechanism and function, as well as the methods of research.
Assuntos
Caenorhabditis elegans/genética , Regulação da Expressão Gênica , MicroRNAs/genética , Animais , Arabidopsis/genética , Drosophila/genética , Humanos , MicroRNAs/isolamento & purificação , Tetrahymena/genéticaRESUMO
Activation tagging is a new method for isolation and functional identification. It can generate dominant gain-of-function mutants by overexpression of a particular endogenous gene. Due to this special characteristics of activation tagging,this method has been a powerful tool for new gene discovery and gene functional analysis. This paper reviewed the principle and study conditions of activation tagging,as well as its use in plant genetic engineering.