TY - JOUR
T1 - Preferential up-regulation of G2/M phase-specific genes by overexpression of the hyperactive form of NtmybA2 lacking its negative regulation domain in tobacco BY-2 cells1[W]
AU - Kato, Kiichi
AU - Gàlis, Ivan
AU - Suzuki, Shiori
AU - Araki, Satoshi
AU - Demura, Taku
AU - Criqui, Marie Claire
AU - Potuschak, Thomas
AU - Genschik, Pascal
AU - Fukuda, Hiroo
AU - Matsuoka, Ken
AU - Ito, Masaki
PY - 2009/4
Y1 - 2009/4
N2 - Many G2/M phase-specific genes in plants contain mitosis-specific activator (MSA) elements, which act as G2/M phasespecific enhancers and bind with R1R2R3-Myb transcription factors. Here, we examined the genome-wide effects of NtmybA2 overexpression, one of the R1R2R3-Myb transcription factors in tobacco (Nicotiana tabacum). We used a custom-made 16-K cDNA microarray for comparative transcriptome analysis of transgenic tobacco BY-2 cell lines that overexpress NtmybA2 or its truncated hyperactive form. The microarray was also used to determine the transcript profile during the cell cycle in synchronized cultures of BY-2 cells. Combined microarray data from transgenic lines and synchronized cells revealed that overexpression of the truncated hyperactive form of NtmybA2, but not its full-length form, preferentially up-regulated many G2/M phase-specific genes in BY-2 cells. We determined promoter sequences of several such up-regulated genes and showed that all contain MSA-like motifs in the proximal regions of their promoters. One of the up-regulated genes, NtE2C, encoding for cyclin-specific ubiquitin carrier proteins, contained a single functional MSA-like motif, which specifically controlled the expression of a reporter gene in the G2/M phase in BY-2 cells. Furthermore, a genomic footprint experiment showed that the MSA element in the NtE2C promoter interacted with nuclear proteins in vivo. Therefore, we propose that the transcription of many G2/M phase-specific genes in tobacco is positively regulated by NtmybA2, in most cases through direct binding to the MSA elements.
AB - Many G2/M phase-specific genes in plants contain mitosis-specific activator (MSA) elements, which act as G2/M phasespecific enhancers and bind with R1R2R3-Myb transcription factors. Here, we examined the genome-wide effects of NtmybA2 overexpression, one of the R1R2R3-Myb transcription factors in tobacco (Nicotiana tabacum). We used a custom-made 16-K cDNA microarray for comparative transcriptome analysis of transgenic tobacco BY-2 cell lines that overexpress NtmybA2 or its truncated hyperactive form. The microarray was also used to determine the transcript profile during the cell cycle in synchronized cultures of BY-2 cells. Combined microarray data from transgenic lines and synchronized cells revealed that overexpression of the truncated hyperactive form of NtmybA2, but not its full-length form, preferentially up-regulated many G2/M phase-specific genes in BY-2 cells. We determined promoter sequences of several such up-regulated genes and showed that all contain MSA-like motifs in the proximal regions of their promoters. One of the up-regulated genes, NtE2C, encoding for cyclin-specific ubiquitin carrier proteins, contained a single functional MSA-like motif, which specifically controlled the expression of a reporter gene in the G2/M phase in BY-2 cells. Furthermore, a genomic footprint experiment showed that the MSA element in the NtE2C promoter interacted with nuclear proteins in vivo. Therefore, we propose that the transcription of many G2/M phase-specific genes in tobacco is positively regulated by NtmybA2, in most cases through direct binding to the MSA elements.
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U2 - 10.1104/pp.109.135582
DO - 10.1104/pp.109.135582
M3 - Article
C2 - 19244455
AN - SCOPUS:65249090772
VL - 149
SP - 1945
EP - 1957
JO - Plant Physiology
JF - Plant Physiology
SN - 0032-0889
IS - 4
ER -