Arabidosis

Well-defined motifs often make it easy to investigate protein function and localization. In plants, peroxisomal proteins are guided to peroxisomes mainly by a conserved type 1 (PTS1) or type 2 (PTS2) targeting signal, and the PTS1 motif is commonly used for peroxisome targeting protein prediction. Currently computational prediction of peroxisome targeted PTS1-type proteins are mostly based on the 3 amino acids PTS1 motif and the adjacent sequence which is less than 14 amino acid residue in length. The potential contribution of the adjacent sequences beyond this short region has never been well investigated in plants...

Alcohol dehydrogenases (ADH) catalyze the interconversion between alcohols and aldehydes with the reduction of nicotinamide adenine dinucleotide (NAD(+)) to NADH. In this study, for the first time we report an over-expression and purification strategy for the Arabidosis thaliana ADH (AtADH), and characterize its enzymatic properties. AtADH was expressed in an Escherichia coli system, the polyhistidine-tag was removed after the recombinant AtADH protein was purified by metal chelating affinity chromatography...

Formation of glycerol as by-product of amino acid production by Corynebacterium glutamicum has been observed under certain conditions, but the enzyme(s) involved in its synthesis from glycerol-3-phosphate were not known. It was shown here that cg1700 encodes an enzyme active as a glycerol-3-phosphatase (GPP) hydrolyzing glycerol-3-phosphate to inorganic phosphate and glycerol. GPP was found to be active as a homodimer. The enzyme preferred conditions of neutral pH and requires Mg²⁺ or Mn²⁺ for its activity...

Despite the high isoform multiplicity of aquaporins in plants, with 35 homologues including 13 plasma membrane intrinsic proteins (PIPs) in Arabidosis thaliana, the individual and integrated functions of aquaporins under various physiological conditions remain unclear. To better understand aquaporin functions in plants under various stress conditions, we examined transgenic Arabidopsis and tobacco plants that constitutively overexpress Arabidopsis PIP1;4 or PIP2;5 under various abiotic stress conditions. No significant differences in growth rates and water transport were found between the transgenic and wild-type plants when grown under favorable growth conditions...

* The blue light photoreceptor phototropin-1 has been shown to enhance fitness in Arabidosis thaliana under field conditions. Here, we ask whether performance consequences of phototropin-1 reflect its impact on root growth and drought tolerance. * We used a PHOT1-GFP gene construct to test whether phototropin-1 abundance in roots is highest at shallow soil depths where light penetration is greatest. We then compared root growth efficiency and size at maturity between individuals with and without functional phototropin-1...

Exon shuffling is an essential molecular mechanism for the formation of new genes. Many cases of exon shuffling have been reported in vertebrate genes. These discoveries revealed the importance of exon shuffling in the origin of new genes. However, only a few cases of exon shuffling were reported from plants and invertebrates, which gave rise to the assertion that the intron-mediated recombination mechanism originated very recently. We focused on the origin of new genes by exon shuffling and retroposition. We will first summarize our experimental work, which revealed four new genes in Drosophila, plants, and humans...

In order to understand the molecular mechanisms which are responsible for desiccation tolerance in the resurrection plant Craterostigma plantagineum Hochst. a thorough analysis of the CDeT11-24 gene family was performed. CDeT11-24 comprises a small gene family whose genes are expressed in response to dehydration, salt stress and abscisic acid (ABA) treatment in leaves. The gene products are constitutively expressed in roots and disappear only when the plants are transferred to water. It is therefore suggested that the proteins are involved in sensing water status...

Hypocotyls of dark-grown seedlings of Arabidosis thaliana exhibit a strong negative gravitropism, which is reduced by red and also by long-wavelength, far-red light treatments. Light treatments using phytochrome A (phyA)- and phytochrome B (phyB)-deficient mutants showed that this response is controlled by phyB in a red/far-red reversible way, and by phyA in a non-reversible, very-low-fluence response. Crosses of the previously analyzed phyB-1 allele (in the ecotype Landsberg erecta background) to the ecotype Nossen wild-type (WT) background resulted in a WT-like negative gravitropism in darkness, indicating that the previously described gravitropic randomization observed with phyB-1 in the dark is likely due to a second mutation independent of that in the PHYB gene...