Summary During embryogenesis, plants are thought to use a mechanism that allows the suspensor to maintain its identity. Here, we reported that RPL18a is involved in this mechanism in Arabidopsis thaliana. The suspenso...Summary During embryogenesis, plants are thought to use a mechanism that allows the suspensor to maintain its identity. Here, we reported that RPL18a is involved in this mechanism in Arabidopsis thaliana. The suspensor cells proliferated in rp118aB and formed a multicellular structure rather than undergo pro- grammed cell death, as in wild type. Suspensors of rpl18a expressed the embryo proper marker, DRN：： GFP, but not the suspensor marker, WOX8：：GFP. In addition, auxin accumulated throughout the suspensors of rpl18a proembryos. Suspensor-specific expression of RPL18a could rescue the cell proliferation defects in rpl18a suspensors. These findings supported a role for RPL18a in maintaining suspensor identity.展开更多
The embryo structure of two apomictir lines 296B and SSA-1 has been com-pared in present paper. The apomictic embryo has the same character of lacking (or short) sus-pensor in sorghum,otherwise,the sexual embryo has a...The embryo structure of two apomictir lines 296B and SSA-1 has been com-pared in present paper. The apomictic embryo has the same character of lacking (or short) sus-pensor in sorghum,otherwise,the sexual embryo has a long suspensor in the same species. This character as an index of judgement on apomxis was discussed. The same of unsexual embryos in the lack of suspensor suggested that there were some relationships between non-zagotic embryos.展开更多
利用透射电镜技术研究了大车前(Plantago major L.)合子及其原胚发育特点。结果如下:大车前胚胎发育类型为柳叶菜类型。合子发育过程中,合点端的细胞壁逐渐形成,合子体积增大,极性增强,质体内贮藏淀粉。合子分裂通常发生在初生胚乳核分...利用透射电镜技术研究了大车前(Plantago major L.)合子及其原胚发育特点。结果如下:大车前胚胎发育类型为柳叶菜类型。合子发育过程中,合点端的细胞壁逐渐形成,合子体积增大,极性增强,质体内贮藏淀粉。合子分裂通常发生在初生胚乳核分裂之后,第1次横分裂形成基细胞和顶细胞。基细胞经多次分裂形成单列细胞构成发达的胚柄;顶细胞多次分裂形成胚体,胚体细胞核大,核仁明显,细胞器的种类与数量多,呈现旺盛分生能力,具有很高的代谢活性。原胚发育过程中,小球胚初期,胚胎发育的营养物质主要来自合子储存的以及胚柄吸收并转运的营养物质;小球胚至中球胚期,胚柄组织迅速发育,依赖发达的胚柄自珠被组织吸收营养物质并转运至胚体;大球胚后期,胚柄开始解体,胚体外围细胞吸收胚乳的降解物作为胚胎发育所需营养物质。展开更多
基金supported by the National Natural Science Foundation of China(31570317 and 31270362)
文摘Summary During embryogenesis, plants are thought to use a mechanism that allows the suspensor to maintain its identity. Here, we reported that RPL18a is involved in this mechanism in Arabidopsis thaliana. The suspensor cells proliferated in rp118aB and formed a multicellular structure rather than undergo pro- grammed cell death, as in wild type. Suspensors of rpl18a expressed the embryo proper marker, DRN：： GFP, but not the suspensor marker, WOX8：：GFP. In addition, auxin accumulated throughout the suspensors of rpl18a proembryos. Suspensor-specific expression of RPL18a could rescue the cell proliferation defects in rpl18a suspensors. These findings supported a role for RPL18a in maintaining suspensor identity.
文摘The embryo structure of two apomictir lines 296B and SSA-1 has been com-pared in present paper. The apomictic embryo has the same character of lacking (or short) sus-pensor in sorghum,otherwise,the sexual embryo has a long suspensor in the same species. This character as an index of judgement on apomxis was discussed. The same of unsexual embryos in the lack of suspensor suggested that there were some relationships between non-zagotic embryos.
文摘利用透射电镜技术研究了大车前(Plantago major L.)合子及其原胚发育特点。结果如下:大车前胚胎发育类型为柳叶菜类型。合子发育过程中,合点端的细胞壁逐渐形成,合子体积增大,极性增强,质体内贮藏淀粉。合子分裂通常发生在初生胚乳核分裂之后,第1次横分裂形成基细胞和顶细胞。基细胞经多次分裂形成单列细胞构成发达的胚柄;顶细胞多次分裂形成胚体,胚体细胞核大,核仁明显,细胞器的种类与数量多,呈现旺盛分生能力,具有很高的代谢活性。原胚发育过程中,小球胚初期,胚胎发育的营养物质主要来自合子储存的以及胚柄吸收并转运的营养物质;小球胚至中球胚期,胚柄组织迅速发育,依赖发达的胚柄自珠被组织吸收营养物质并转运至胚体;大球胚后期,胚柄开始解体,胚体外围细胞吸收胚乳的降解物作为胚胎发育所需营养物质。
