组氨酸(L-Histidine)对小麦根尖细胞生长和畸变的影响

The Effects of L-Histidine on the Growth and Aberration in Root-tip Meristematic Cells of Triticum aestivum L.

以普通小麦为材料,用不同浓度组氨酸(L-Histidine)处理萌发的种子24h,采用形态学、细胞生物学、分子生物学等研究方法探究L-Histidine对小麦根尖的影响.结果显示,经过L-Histidine处理,小麦根尖生长受到抑制,细胞分裂指数下降,出现染色体畸变、基因组DNA序列改变、rdr基因的表达下调等.表明L-Histidine处理使细胞分裂被阻断在G1-S转换期,DNA合成受阻并导致其序列和染色体结构被破坏,最终抑制小麦根的生长.

Germinated common wheat seeds were treated with different concentrations of L-Histidine for 24h to understand the statue of root growth, mitotic index, chromosome aberrations, changes in DNA sequence and rdr gene expression. After the treatment, it was shown that the root growth was inhibited along with the mitotic index was decreased. Chromosomal aberrations, changes of genomic DNA sequence were also indicated and the expression of rdr gene was down-regulated. Our results demonstrate, for the first time, that L-Histidine can block the cell division during the G1-S transition so that DNA synthesis is inhibited, DNA sequence and chromosome structure are damaged and at last, the root growth is inhibited.