TY - JOUR
T1 - The distribution of different classes of nuclear localization signals (NLSs) in diverse organisms and the utilization of the minor NLS-binding site in plant nuclear import factor importin-α
AU - Chang, Chiung Wen
AU - Couñago, Rafael Miguez
AU - Williams, Simon J.
AU - Boden, Mikael
AU - Kobe, Bostjan
PY - 2013/10
Y1 - 2013/10
N2 - The specific recognition between the import receptor importin-α and the nuclear localization signals (NLSs) is crucial to ensure the selective transport of cargoes into the nucleus. NLSs contain one or two clusters of positively-charged amino-acids, which usually bind to the major (monopartite NLSs) or both minor and major NLS-binding sites (bipartite NLSs). In our recent study, we determined the structure of importin-α1a from rice (Oryza sativa), and made two observations that suggest an increased utilization of the minor NLS-binding site in this protein. First, unlike the mammalian protein, both the major and minor NLS-binding sites are auto-inhibited in the unliganded rice protein. Second, we showed that NLSs of the 'plant-specific' class preferentially bind to the minor NLS-binding site of rice importin-α. Here, we show that a distinct group of 'minor site-specific' NLSs also bind to the minor site of the rice protein. We further show a greater enrichment of proteins containing these plant-specific' and 'minor site-specific' NLSs in the rice proteome. However, the analysis of the distribution of different classes of NLSs in diverse eukaryotes shows that in all organisms, the minor site-specific NLSs are much less prevalent than the classical monopartite and bipartite NLSs.
AB - The specific recognition between the import receptor importin-α and the nuclear localization signals (NLSs) is crucial to ensure the selective transport of cargoes into the nucleus. NLSs contain one or two clusters of positively-charged amino-acids, which usually bind to the major (monopartite NLSs) or both minor and major NLS-binding sites (bipartite NLSs). In our recent study, we determined the structure of importin-α1a from rice (Oryza sativa), and made two observations that suggest an increased utilization of the minor NLS-binding site in this protein. First, unlike the mammalian protein, both the major and minor NLS-binding sites are auto-inhibited in the unliganded rice protein. Second, we showed that NLSs of the 'plant-specific' class preferentially bind to the minor NLS-binding site of rice importin-α. Here, we show that a distinct group of 'minor site-specific' NLSs also bind to the minor site of the rice protein. We further show a greater enrichment of proteins containing these plant-specific' and 'minor site-specific' NLSs in the rice proteome. However, the analysis of the distribution of different classes of NLSs in diverse eukaryotes shows that in all organisms, the minor site-specific NLSs are much less prevalent than the classical monopartite and bipartite NLSs.
KW - Arabidopsis thaliana
KW - Importin-α
KW - Nuclear localization signal
KW - Nuclear-cyto-plasmic transport
KW - Oryza sativa
UR - http://www.scopus.com/inward/record.url?scp=84885202787&partnerID=8YFLogxK
U2 - 10.4161/psb.25976
DO - 10.4161/psb.25976
M3 - Article
SN - 1559-2316
VL - 8
JO - Plant Signaling and Behavior
JF - Plant Signaling and Behavior
IS - 10
ER -