cDNA cloning, genomic organization and expression analysis during somatic embryogenesis of the translationally controlled tumor protein (TCTP) gene from Japanese larch (Larix leptolepis).
A full-length cDNA and genomic sequences of a translationally controlled tumor protein (TCTP) gene were isolated from Japanese larch (Larix leptolepis) and designated LaTCTP. The length of the cDNA was 1, 043 bp and contained a 504 bp open reading frame that encodes a predicted protein of 167 amino acids, characterized by two signature sequences of the TCTP protein family. Analysis of the LaTCTP gene structure indicated four introns and five exons, and it is the largest of all currently known TCTP genes in plants. The 5'-flanking promoter region of LaTCTP was cloned using an improved TAIL-PCR technique. In this region we identified many important potential cis-acting elements, such as a Box-W1 (fungal elicitor responsive element), a CAT-box (cis-acting regulatory element related to meristem expression), a CGTCA-motif (cis-acting regulatory element involved in MeJA-responsiveness), a GT1-motif (light responsive element), a Skn-1-motif (cis-acting regulatory element required for endosperm expression) and a TGA-element (auxin-responsive element), suggesting that expression of LaTCTP is highly regulated. Expression analysis demonstrated ubiquitous localization of LaTCTP mRNA in the roots, stems and needles, high mRNA levels in the embryonal-suspensor mass (ESM), browning embryogenic cultures and mature somatic embryos, and low levels of mRNA at day five during somatic embryogenesis. We suggest that LaTCTP might participate in the regulation of somatic embryo development. These results provide a theoretical basis for understanding the molecular regulatory mechanism of LaTCTP and lay the foundation for artificial regulation of somatic embryogenesis.
Laboratory of Cell Biology, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, PR China.
Li-Feng
LF
Zhang
Wan-Feng
WF
Li
Su-Ying
SY
Han
Wen-Hua
WH
Yang
Li-Wang
LW
Qi
D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D028221:Larix / Q000235:genetics*; D008969:Molecular Sequence Data; D016366:Open Reading Frames; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D058439:Plant Somatic Embryogenesis Techniques; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011487:Protein Conformation; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA
D018076:DNA, Complementary; D010940:Plant Proteins; D012333:RNA, Messenger
2,4-D; 2,4-dichlorophenoxyacetic acid; 6-Benzylaminopurine; ABA; BA; ESM; EST; FPNI-PCR; Fusion primer and nested integrated PCR; GO; GSP; Genomic organization; Larix leptolepis; NFLESB; National Forest Larix Eugenic Species Base; ORF; PCD; Real-time quantitative PCR; Somatic embryogenesis; TCTP; Translationally controlled tumor protein; UTR; abscisic acid; embryonal-suspensor mass; expressed sequence tag; gene ontology; gene-specific primers; open reading frame; programmed cell death; qRT-PCR; real-time quantitative PCR; translationally controlled tumor protein; untranslated region