Concurrent overexpression of amino acid permease AAP1(3a) and SUT1 sucrose transporter in pea resulted in increased seed number and changed cytokinin and protein levels

The legume Oxytropis sericea hosts a fungal endophyte, Alternaria oxytropis, which produces secondary metabolites (SM), including the toxin swainsonine. Polyketide synthase (PKS) and non-ribosomal peptide synthase (NRPS) enzymes are associated with biosynthesis of fungal SM. To better understand the origins of the SM, an unannotated genome of A. oxytropis was assessed for protein sequences similar to known PKS and NRPS enzymes of fungi. Contigs exhibiting identity with known genes were analyzed at nucleotide and protein levels using available databases. Software were used to identify PKS and NRPS domains and predict identity and function. Confirmation of sequence for selected gene sequences was accomplished using PCR. Thirteen PKS, 5 NRPS, and 4 PKS-NRPS hybrids were identified and characterized with functions including swainsonine and melanin biosynthesis. Phylogenetic relationships among closest amino acid matches with Alternaria spp. were identified for seven highly conserved PKS and NRPS, including melanin synthesis. Three PKS and NRPS were most closely related to other fungi within the Pleosporaceae family, while five PKS and PKS-NRPS were closely related to fungi in the Pleosporales order. However, seven PKS and PKS-NRPS showed no identity with fungi in the Pleosporales or the class Dothideomycetes, suggesting a different evolutionary origin for those genes.

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Yeast NOP2 encodes an essential nucleolar protein with homology to a human proliferation marker.

The Journal of Cell Biology ◽

10.1083/jcb.127.6.1799 ◽

1994 ◽

Vol 127 (6) ◽

pp. 1799-1813 ◽

Cited By ~ 49

Author(s):

E de Beus ◽

J S Brockenbrough ◽

B Hong ◽

J P Aris

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Ribosomal Protein ◽

Nucleolar Protein ◽

Mrna Levels ◽

Multicopy Plasmid ◽

Yeast Saccharomyces Cerevisiae ◽

Protein Levels ◽

Significant Amino Acid Sequence ◽

Ribosomal Protein L3

We have isolated a gene (NOP2) encoding a nucleolar protein during a search for previously unidentified nuclear proteins in the yeast Saccharomyces cerevisiae. The protein encoded by NOP2 (Nop2p) has a predicted molecular mass of 70 kD, migrates at 90 kD by SDS-PAGE, and is essential for cell viability. Nop2p shows significant amino acid sequence homology to a human proliferation-associated nucleolar protein, p120. Approximately half of Nop2p exhibits 67% amino acid sequence identity to p120. Analysis of subcellular fractions indicates that Nop2p is located primarily in the nucleus, and nuclear fractionation studies suggest that Nop2p is associated with the nucleolus. Indirect immunofluorescence localization of Nop2p shows a nucleolar-staining pattern, which is heterogeneous in appearance, and a faint staining of the cytoplasm. The expression of NOP2 during the transition from stationary phase growth arrest to rapid growth was measured, and compared to the expression of TCM1, which encodes the ribosomal protein L3. Nop2p protein levels are markedly upregulated during the onset of growth, compared to the levels of ribosomal protein L3, which remain relatively constant. NOP2 mRNA levels also increase during the onset of growth, accompanied by a similar increase in the levels of TCM1 mRNA. The consequences of overexpressing NOP2 from the GAL10 promoter on a multicopy plasmid were investigated. Although NOP2 overexpression produced no discernible growth phenotype and had no effect on ribosome subunit synthesis, overexpression was found to influence the morphology of the nucleolus, as judged by electron microscopy. Overexpression caused the nucleolus to become detached from the nuclear envelope and to become more rounded and/or fragmented in appearance. These findings suggest roles for NOP2 in nucleolar function during the onset of growth, and in the maintenance of nucleolar structure.

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The amino acid permease AAP8 is important for early seed development in Arabidopsis thaliana

Planta ◽

10.1007/s00425-007-0527-x ◽

2007 ◽

Vol 226 (4) ◽

pp. 805-813 ◽

Cited By ~ 73

Author(s):

Roberto Schmidt ◽

Harald Stransky ◽

Wolfgang Koch

Keyword(s):

Arabidopsis Thaliana ◽

Amino Acid ◽

Seed Development ◽

Amino Acid Permease ◽

Early Seed Development

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Intracellular trafficking and ubiquitination of the Schizosaccharomyces pombe amino acid permease Aat1p

Microbiology ◽

10.1099/mic.0.053389-0 ◽

2012 ◽

Vol 158 (3) ◽

pp. 659-673 ◽

Cited By ~ 11

Author(s):

Mai Nakase ◽

Yukiko Nakase ◽

Soracom Chardwiriyapreecha ◽

Yoshimi Kakinuma ◽

Tomohiro Matsumoto ◽

...

Keyword(s):

Amino Acid ◽

Schizosaccharomyces Pombe ◽

Intracellular Trafficking ◽

Amino Acid Permease

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Incorporation of a charged amino acid into the membrane-spanning domain blocks cell surface transport but not membrane anchoring of a viral glycoprotein

Molecular and Cellular Biology ◽

10.1128/mcb.5.6.1442-1448.1985 ◽

1985 ◽

Vol 5 (6) ◽

pp. 1442-1448

Author(s):

G A Adams ◽

J K Rose

Keyword(s):

Amino Acid ◽

Cell Surface ◽

G Protein ◽

Abnormal Behavior ◽

Animal Cells ◽

Viral Glycoprotein ◽

Protein Levels ◽

Membrane Spanning ◽

Membrane Anchoring ◽

Isoleucine Residue

The membrane-spanning domain of the vesicular stomatitis virus glycoprotein (G protein) consists of a continuous stretch of 20 uncharged and mostly hydrophobic amino acids. We examined the effects of two mutations which change the amino acid sequence in this domain. These mutations were generated by oligonucleotide-directed mutagenesis of a cDNA clone encoding the G protein, and the altered G proteins were then expressed in animal cells. Replacement of an isoleucine residue in the center of this domain with a strongly polar but uncharged amino acid (glutamine) had no effect on membrane anchoring or transport of the protein to the cell surface. Replacement of this same isoleucine residue with a charged amino acid (arginine) generated a G protein that still spanned intracellular membranes but was not transported efficiently to the cell surface. The protein accumulated in the Golgi region in about 50% of the cells, and about 20% of the cells had detectable protein levels in a punctate pattern on the cell surface. In the remaining cells the protein accumulated in a vesicular pattern throughout the cytoplasm. Models which might explain the abnormal behavior of this protein are discussed.

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Transcription and Translation of the Sex Message in the Smut Fungus Ustilago Violacea

Journal of Cell Science ◽

10.1242/jcs.16.1.49 ◽

1974 ◽

Vol 16 (1) ◽

pp. 49-62

Author(s):

J. E. CUMMINS ◽

A. W. DAY

Keyword(s):

Amino Acid ◽

Dna Replication ◽

Information Exchange ◽

Plasma Membranes ◽

Cellular Protein ◽

Mating Activity ◽

Ustilago Violacea ◽

Protein Levels ◽

Amino Acid Turnover ◽

Mating Conditions

In Ustilago violacea conjugation involves a period of courtship followed by the cooperative assembly of a conjugation tube between paired sporidia of opposite mating type. During courtship information is exchanged between the paired sporidia directing transcription and translation of a ‘sex message’. This information exchange is completed even though the plasma membranes and walls of the mating sporidia remain intact until after the sex message has been translated. Once translation is completed the copulatory organelle is assembled. Inhibitor studies show that translation of specific mRNA species (sex message) is essential during the 3-4 h period of courtship prior to assembly and that transcription of this sex message is completed 15-30 min prior to the completion of translation. Amino acid incorporation studies show that even though the cellular protein levels remain constant during courtship there is extensive amino acid turnover as the sporidia adjust to mating conditions. However, an enhancement of amino acid turnover by mating, in contrast to unmixed sporidia, is not detectable. Prototrophic strains continue to synthesize stable RNA during courtship while amino acid auxotrophs discontinue stable RNA synthesis immediately on transfer to mating conditions. Both prototrophs and auxotrophs show extensive RNA turnover during courtship but a specific enhancement of turnover due to mating activity is not detectable from the labelling pattern alone. A round of DNA replication may be completed during courtship but mating activity does not influence the gross pattern of DNA replication in either of the mating types.

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