Batschauer A, Ehmann B, Schäfer E
Institut für Biologie II der Albert-Ludwigs-Universität, Freiburg, Germany.
Plant Mol Biol. 1991 Feb;16(2):175-85. doi: 10.1007/BF00020550.
Genomic DNA from mustard was cloned in EMBL4 and screened for chalcone synthase (CHS) genes using a heterologous cDNA probe from parsley. Two clones which hybridized with the parsley cDNA probe were isolated. They showed different restriction patterns. One clone was sequenced and identified as a CHS gene by sequence comparison with published CHS sequences. The sequence of the coding region is 1188 bp, and encodes a protein of 43 kDa. The start-point of transcription was determined by primer extension. The sequence of 0.9 kbp at the 5' end of the transcription start and part of the noncoding 3' of this gene were also determined. The coding sequence is interrupted by a single intron of 523 bp. The coding and the noncoding 5' sequence of this gene was compared with CHS genes from other species. A very high homology was found with the Arabidopsis CHS coding region. A sequence motif (CACGTGT) which is present in most rbcS and all CHS upstream regions, and which specifically binds a protein factor from plant nuclear extracts, is also present in the upstream region of the mustard CHS gene. Measurements of CHS transcript levels show that phytochrome controls expression of this gene in cotyledons of mustard seedlings; however, blue/UV-light photoreceptors control expression in later stages of development.
从芥菜中提取的基因组DNA被克隆到EMBL4中，并使用来自欧芹的异源cDNA探针筛选查尔酮合酶（CHS）基因。分离出两个与欧芹cDNA探针杂交的克隆。它们显示出不同的限制性图谱。对其中一个克隆进行测序，并通过与已发表的CHS序列进行序列比较将其鉴定为CHS基因。编码区序列为1188 bp，编码一个43 kDa的蛋白质。转录起始点通过引物延伸确定。还确定了转录起始5'端0.9 kbp的序列以及该基因非编码3'端的部分序列。编码序列被一个523 bp的单一内含子中断。将该基因的编码序列和非编码5'序列与其他物种的CHS基因进行比较。发现与拟南芥CHS编码区具有非常高的同源性。芥菜CHS基因的上游区域也存在一个序列基序（CACGTGT），该基序存在于大多数rbcS和所有CHS上游区域，并且能特异性结合植物核提取物中的一种蛋白质因子。CHS转录水平的测量表明，光敏色素控制芥菜幼苗子叶中该基因的表达；然而，蓝光/紫外光光感受器在发育后期控制该基因的表达。
