Authors:Gyöngyvér Gell, Kathrin Petrik, and E. Balázs
During our recent four years epidemiological studies ofMaize dwarf mosaic virus (MDMV) populations in Hungary, when 86 virus isolates were collected and analysed, a unique nucleic acid sequence variant was found in the 3’end region of the viral genome. According to our sequence studies, which also included all available MDMV sequences from different databanks, the coat protein region of the viral genome prooved to be quite identical. However, in several cases an insertion was located in the same position of the coat protein region. In the unique sequence variant we also found a 27 nt deletion in addition to the insertion. According to the extensive sequence search this deletion is unique and have been located only in two other potyvirus coat protein regions, while never in the case of MDMV. The potential role of this deletion in the virus infectivity, replication or other biological characteristics is discussed.
Authors:Gyöngyvér Gell, Kathrin Petrik, Endre Sebestyén, and Ervin Balázs
Petrik , K. – Sebestyén , E. – Gell , G. – Balázs , E. : 2010 . Natural insertions within the N-terminal region of the coat protein of Maize dwarf mosaic potyvirus (MDMV) have an effect on the RNA stability
Authors:Markus Krohn, Thomas Wanek, Marie-Claude Menet, Andreas Noack, Xavier Declèves, Oliver Langer, Wolfgang Löscher, and Jens Pahnke
introduction of the human ABCB1 CDS into the gene's ATG start codon in exon 2. The mouse Abcb1b gene was partially deleted by insertion of a hygromycin cassette replacing exons 3 and 4 to ensure that only the human gene would be expressed. At purchase from
Authors:Anna Tóth, Katalin Fodor, P. Blazsó, I. Cserpán, Tünde Praznovszky, V. Tubak, A. Udvardy, Gy. Hadlaczky, and R. Katona
Direct reprogramming of mouse fibroblasts into induced pluripotent stem cells (iPS) was achieved recently by overexpression of four transcription factors encoded by retroviral vectors. Most of the virus vectors, however, may cause insertional mutagenesis in the host genome and may also induce tumor formation. Therefore, it is very important to discover novel and safer, non-viral reprogramming methods. Here we describe the reprogramming of somatic cells into iPS cells by a novel protein-based technique. Engineered Oct4, Sox2 and Klf4 transcription factors carrying an N-terminal Flag-tag and a C-terminal polyarginine tail were synthesized by a recently described mammalian artificial chromosome expression system (ACEs). This system is suitable for the high-level production of recombinant proteins in mammalian tissue culture cells. Recombinant proteins produced in this system contain all the post-translational modifications essential for the stability and the authentic function of the proteins. The engineered Oct4, Sox2 and Klf4 proteins efficiently induced the reprogramming of mouse embryonic fibroblasts by means of protein transduction. This novel method allows for the generation of iPS cells, which may be suitable for therapeutic applications in the future.
Authors:Z.L. Li, H.Y. Li, G. Chen, X.J. Liu, C.L. Kou, S.Z. Ning, Z.W. Yuan, M. Hao, D.C. Liu, and L.Q. Zhang
Seven Glu-A1m allelic variants of the Glu-A1mx genes in Triticum monococcum ssp. monococcum, designated as 1Ax2.1a, 1Ax2.1b, 1Ax2.1c, 1Ax2.1d, 1Ax2.1e, 1Ax2.1f, and 1Ax2.1g were characterized. Their authenticity was confirmed by successful expression of the coding regions in E. coli, and except for the 1Ax2.1a with the presence of internal stop codons at position of 313 aa, all correspond to the subunit in seeds. However, all the active six genes had a same DNA size although their encoding subunits showed different molecular weight. Our study indicated that amino acid residue substitutions rather than previously frequently reported insertions/deletions played an important role on the subunit evolution of these Glu-A1mx alleles. Since variation in the Glu-A1x locus in common wheat is rare, these novel genes at the Glu-A1mx can be used as candidate genes for further wheat quality improvement.
High-molecular-weight glutenin subunits (HMW-GSs) are important seed storage proteins associated with bread-making quality in common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD). Variation in the Glu-A1x locus in common wheat is scare. Diploid Triticum monococcum ssp. monococcum (2n = 2x = 14, AmAm) is the first cultivated wheat. In the present study, allelic variations at the Glu-A1mx locus were systematically investigated in 197 T. monococcum ssp. monococcum accessions. Out of the 8 detected Glu-A1mx alleles, 5 were novel, including Glu-A1m-b, Glu-A1m-c, Glu-A1m-d, Glu-A1m-g, and Glu-A1m-h. This diversity is higher than that of common wheat. Compared with 1Ax1 and 1Ax2*, which are present in common wheat, these alleles contained three deletions/insertions as well as some single nucleotide polymorphism variations that might affect the elastic properties of wheat flour. New variations in T. monococcum probably occurred after the divergence between A and Am and are excluded in common wheat populations. These allelic variations could be used as novel resources to further improve wheat quality.
Forsbach, A., Schubert, D., Lechtenberg, B., Gils, M., Schmidt, R. 2003. A comprehensive characterization of single-copy T-DNA insertions in the
genome. Plant Molecular Biology