Apospory appears to accelerate onset of meiosis and sexual embryo sac formation in sorghum ovules.
Apospory appears to accelerate onset of meiosis and sexual embryo sac formation in sorghum ovules.
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DOI：
10.1186/1471-2229-11-9
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发表时间：
2011-01-11
影响因子：
5.3
通讯作者：
Naumova TN
中科院分区：
文献类型：
--
作者：
Carman JG;Jamison M;Elliott E;Dwivedi KK;Naumova TN
在配子体无融合生殖体的胚珠中形成遗传上未减数（2n）的胚囊（ES），其中的2n个卵孤雌生殖地发育成胚。在许多无融合生殖体中，2n ES在胚珠发育过程中早熟形成。减数分裂和有性ES的形成是否也在兼性无融合生殖（能够无融合生殖和有性生殖）中早熟发生尚未研究。我们确定了569个两色Sorcobicolor基因型的减数分裂和有性ES形成的起始时间，其中许多产生了2n ES facultimate。减数分裂和性ES形成的开始时间，相对于胚珠发育的基因型差异是非常显着的。性生殖系发育时间的变化的一个主要来源是无融合生殖ES的存在或不存在，在某些基因型中，无融合生殖ES由珠心细胞（无孢子生殖）形成。产生这些无孢子ES的基因型经历减数分裂和有性ES形成早熟。无孢子体ES的形成在亚种中最为普遍。verticilliflorum和subsp.双色的这在陆地竞赛中并不常见。本研究增加了减数分裂和有性ES形成的花诱导，无融合生殖ES形成，孤雌生殖过程中观察到的无融合生殖植物早熟发生。这些事件的时间多样性表明，植物的无融合生殖状态的表观遗传记忆存在于其整个生命周期中，这在多个生命周期阶段触发了加速繁殖的时间上不同的过程。
Genetically unreduced (2n) embryo sacs (ES) form in ovules of gametophytic apomicts, the 2n eggs of which develop into embryos parthenogenetically. In many apomicts, 2n ES form precociously during ovule development. Whether meiosis and sexual ES formation also occur precociously in facultative apomicts (capable of apomictic and sexual reproduction) has not been studied. We determined onset timing of meiosis and sexual ES formation for 569 Sorghum bicolor genotypes, many of which produced 2n ES facultatively. Genotype differences for onset timing of meiosis and sexual ES formation, relative to ovule development, were highly significant. A major source of variation in timing of sexual germline development was presence or absence of apomictic ES, which formed from nucellar cells (apospory) in some genotypes. Genotypes that produced these aposporous ES underwent meiosis and sexual ES formation precociously. Aposporous ES formation was most prevalent in subsp. verticilliflorum and in breeding lines of subsp. bicolor. It was uncommon in land races. The present study adds meiosis and sexual ES formation to floral induction, apomictic ES formation, and parthenogenesis as processes observed to occur precociously in apomictic plants. The temporally diverse nature of these events suggests that an epigenetic memory of the plants' apomixis status exists throughout its life cycle, which triggers, during multiple life cycle phases, temporally distinct processes that accelerate reproduction.
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影响因子：
1.9
作者：
QUARIN, CL
通讯作者：
QUARIN, CL
影响因子：
56.9
作者：
KNOX, RB
通讯作者：
KNOX, RB
影响因子：
2.3
作者：
Peel, MD;Carman, JG;Wang, RRC
通讯作者：
Wang, RRC
影响因子：
5.1
作者：
Menz, MA;Klein, RR;Klein, PE
通讯作者：
Klein, PE
影响因子：
2.3
作者：
Peel, MD;Carman, JG;Leblanc, O
通讯作者：
Leblanc, O