中文摘要：

抗细胞凋亡基因（DAD）是一个高度保守的细胞凋亡抑制基因,在植物生长发育中承担重要功能。为全面了解DAD基因在种子植物中的分布和演化规律,该文利用31种植物的全基因组数据,通过生物信息学手段,深入探讨和分析了不同植物类群中DAD基因的拷贝数目、基因结构和染色体定位,并综合另外7种裸子植物的转录组数据探讨了其在种子植物中的演化趋势。结果表明,DAD基因属于低拷贝基因,在不同种子植物中只具有1–3个拷贝;不同DAD基因编码的氨基酸长度在108–170 aa之间变动。同线性和系统发育分析进一步表明,种子植物DAD基因的演化具有明显的谱系特异性。随机复制和染色体大片段复制及其随后的基因丢失可能是其维持低拷贝的重要方式。

英文摘要：

Defender against apoptotic death （DAD） is a highly conserved cellular apoptosis gene and plays an important role in seed plant growth and development. To fully understand the evolutionary pattern of the DAD gene in seed plants, based on the whole genome data of 31 plants, we analyzed copy number, structure, chromosome location of the DAD genes by using bioinformatics. In addition, along with transcriptome data for seven gymnosperms, we discuss the evolutionary trend of the genes in seed plants. The DAD gene is a low-copy gene with only 1-3 copies in different seed plants, and the length of different DAD protein varies from 108 to 170 aa. Phylogenetic and syntonic analyses further showed that the evolution of the DAD gene in these seed species has a lineage-specific characteristic. Random and block duplication and subsequent gene loss were possibly important ways to maintain the low-copy number of DAD genes in seed plant genomes.