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Title: Identification of nucleosome assembly protein 1 (NAP1) as an interacting partner of plant ribosomal protein S6 (RPS6) and a positive regulator of rDNA transcription

Abstract

The ribosomal protein S6 (RPS6) is a downstream component of the signaling mediated by the target of rapamycin (TOR) kinase that acts as a central regulator of the key metabolic processes, such as protein translation and ribosome biogenesis, in response to various environmental cues. In our previous study, we identified a novel role of plant RPS6, which negatively regulates rDNA transcription, forming a complex with a plant-specific histone deacetylase, AtHD2B. Here we report that the Arabidopsis RPS6 interacts additionally with a histone chaperone, nucleosome assembly protein 1(AtNAP1;1). The interaction does not appear to preclude the association of RPS6 with AtHD2B, as the AtNAP1 was also able to interact with AtHD2B as well as with an RPS6-AtHD2B fusion protein in the BiFC assay and pulldown experiment. Similar to a positive effect of the ribosomal S6 kinase 1 (AtS6K1) on rDNA transcription observed in this study, overexpression or down regulation of the AtNAP1;1 resulted in concomitant increase and decrease, respectively, in rDNA transcription suggesting a positive regulatory role played by AtNAP1 in plant rDNA transcription, possibly through derepression of the negative effect of the RPS6-AtHD2B complex. - Highlights: • Nucleosome assembly protein 1 (AtNAP1) interacts with RPS6 as well as with AtHD2B.more » • rDNA transcription is regulated S6K1. • Overexpression or down regulation of AtNAP1 results in concomitant increase or decrease in rDNA transcription.« less

Authors:
 [1];  [1];  [2];  [1];  [3];  [4];  [1]
  1. Department of Biological Science, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)
  2. (Korea, Republic of)
  3. College of Pharmacy, Sookmyung Women's University, Seoul 140-742 (Korea, Republic of)
  4. Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921 (Korea, Republic of)
Publication Date:
OSTI Identifier:
22458548
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 465; Journal Issue: 2; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ARABIDOPSIS; FLUORESCENCE; PROTEINS; SIGNALS; TRANSCRIPTION

Citation Formats

Son, Ora, Kim, Sunghan, Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Shin, Yun-jeong, Kim, Woo-Young, Koh, Hee-Jong, E-mail: heejkoh@snu.ac.kr, and Cheon, Choong-Ill, E-mail: ccheon@sookmyung.ac.kr. Identification of nucleosome assembly protein 1 (NAP1) as an interacting partner of plant ribosomal protein S6 (RPS6) and a positive regulator of rDNA transcription. United States: N. p., 2015. Web. doi:10.1016/J.BBRC.2015.07.150.
Son, Ora, Kim, Sunghan, Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Shin, Yun-jeong, Kim, Woo-Young, Koh, Hee-Jong, E-mail: heejkoh@snu.ac.kr, & Cheon, Choong-Ill, E-mail: ccheon@sookmyung.ac.kr. Identification of nucleosome assembly protein 1 (NAP1) as an interacting partner of plant ribosomal protein S6 (RPS6) and a positive regulator of rDNA transcription. United States. doi:10.1016/J.BBRC.2015.07.150.
Son, Ora, Kim, Sunghan, Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Shin, Yun-jeong, Kim, Woo-Young, Koh, Hee-Jong, E-mail: heejkoh@snu.ac.kr, and Cheon, Choong-Ill, E-mail: ccheon@sookmyung.ac.kr. 2015. "Identification of nucleosome assembly protein 1 (NAP1) as an interacting partner of plant ribosomal protein S6 (RPS6) and a positive regulator of rDNA transcription". United States. doi:10.1016/J.BBRC.2015.07.150.
@article{osti_22458548,
title = {Identification of nucleosome assembly protein 1 (NAP1) as an interacting partner of plant ribosomal protein S6 (RPS6) and a positive regulator of rDNA transcription},
author = {Son, Ora and Kim, Sunghan and Department of Plant Science, Plant Genomics and Breeding Institute, Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 151-921 and Shin, Yun-jeong and Kim, Woo-Young and Koh, Hee-Jong, E-mail: heejkoh@snu.ac.kr and Cheon, Choong-Ill, E-mail: ccheon@sookmyung.ac.kr},
abstractNote = {The ribosomal protein S6 (RPS6) is a downstream component of the signaling mediated by the target of rapamycin (TOR) kinase that acts as a central regulator of the key metabolic processes, such as protein translation and ribosome biogenesis, in response to various environmental cues. In our previous study, we identified a novel role of plant RPS6, which negatively regulates rDNA transcription, forming a complex with a plant-specific histone deacetylase, AtHD2B. Here we report that the Arabidopsis RPS6 interacts additionally with a histone chaperone, nucleosome assembly protein 1(AtNAP1;1). The interaction does not appear to preclude the association of RPS6 with AtHD2B, as the AtNAP1 was also able to interact with AtHD2B as well as with an RPS6-AtHD2B fusion protein in the BiFC assay and pulldown experiment. Similar to a positive effect of the ribosomal S6 kinase 1 (AtS6K1) on rDNA transcription observed in this study, overexpression or down regulation of the AtNAP1;1 resulted in concomitant increase and decrease, respectively, in rDNA transcription suggesting a positive regulatory role played by AtNAP1 in plant rDNA transcription, possibly through derepression of the negative effect of the RPS6-AtHD2B complex. - Highlights: • Nucleosome assembly protein 1 (AtNAP1) interacts with RPS6 as well as with AtHD2B. • rDNA transcription is regulated S6K1. • Overexpression or down regulation of AtNAP1 results in concomitant increase or decrease in rDNA transcription.},
doi = {10.1016/J.BBRC.2015.07.150},
journal = {Biochemical and Biophysical Research Communications},
number = 2,
volume = 465,
place = {United States},
year = 2015,
month = 9
}
  • Highlights: {yields} Brain-specific angiogenesis inhibitor 2 (BAI2) is a new partner protein for GIP. {yields} BAI2 interaction with GIP was revealed by yeast two-hybrid assay. {yields} Binding of BAI2 to GIP was characterized by NMR, CD and fluorescence. {yields} BAI2 and GIP binding was mediated through the C-terminus of BAI2. -- Abstract: The vast majority of physiological processes in living cells are mediated by protein-protein interactions often specified by particular protein sequence motifs. PDZ domains, composed of 80-100 amino acid residues, are an important class of interaction motif. Among the PDZ-containing proteins, glutaminase interacting protein (GIP), also known as Taxmore » Interacting Protein TIP-1, is unique in being composed almost exclusively of a single PDZ domain. GIP has important roles in cellular signaling, protein scaffolding and modulation of tumor growth and interacts with a number of physiological partner proteins, including Glutaminase L, {beta}-Catenin, FAS, HTLV-1 Tax, HPV16 E6, Rhotekin and Kir 2.3. To identify the network of proteins that interact with GIP, a human fetal brain cDNA library was screened using a yeast two-hybrid assay with GIP as bait. We identified brain-specific angiogenesis inhibitor 2 (BAI2), a member of the adhesion-G protein-coupled receptors (GPCRs), as a new partner of GIP. BAI2 is expressed primarily in neurons, further expanding GIP cellular functions. The interaction between GIP and the carboxy-terminus of BAI2 was characterized using fluorescence, circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy assays. These biophysical analyses support the interaction identified in the yeast two-hybrid assay. This is the first study reporting BAI2 as an interaction partner of GIP.« less
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