In vitro culture promotes partial autonomous endosperm development in unfertilized ovules of wild-type Arabidopsis thaliana var. Columbia
In vitro culture promotes partial autonomous endosperm development in unfertilized ovules of wild-type Arabidopsis thaliana var. Columbia
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DOI：
10.1007/s00497-005-0246-z
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发表时间：
2005-06-01
影响因子：
--
通讯作者：
Bohdanowicz, J
中科院分区：
文献类型：
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作者：
Rojek, J;Kuta, E;Bohdanowicz, J
在体外培养的野生型拟南芥未授粉的子房中，诱导了部分胚乳的发育，没有父本基因组的参与。未授粉的雌蕊在添加6%蔗糖的无激素的Murashige和Skoog(MS)培养基上培养，并添加2 mg氨基嘌呤(BAP；2 mg I~(-1)+NAA(0.1 mg I~(-1))，2，4-二氯苯氧乙酸(2，4-D；外植体暴露于1 h生长素休克20或40 mg I~(-1)，转移到无激素的MS培养基中)。在39个子房(26%)的54个胚珠中，所有培养基均诱导自主胚乳(AE)发育，平均频率为1.4个胚珠/子房。在BAP和NAA两种生长调节剂的组合上，部分胚乳的形成频率最高(59%的子房有胚珠带有AE)，但在无激素的培养基上也能诱导胚乳的发育(20.5%的子房)。根据培养天数和培养基数的不同，AE核的数目从2个到接近50个不等；野生型拟南芥胚乳的典型区域既没有细胞化，也没有分化。无受精胚乳很可能起源于次生核，但从核的大小和结构来看，不能排除极核的参与。体外培养条件不影响卵细胞的增殖。在有自主胚乳核的胚珠和没有胚乳诱导的胚珠中都没有观察到雌核发育的胚胎。
Partial endosperm development without paternal genome involvement was induced in unpollinated ovaries of wild-type Arabidopsis thaliana cultured in vitro. Unpollinated pistils were cultured on hormone-free Murashige and Skoog ( MS) medium with addition of 6% sucrose and supplemented with: benzylaminopurine ( BAP; 2 mg I-1) combined with naphthylacetic acid ( NAA; 0.1 mg I-1), 2,4- dichlorophenoxyacetic acid ( 2,4- D; explants exposed to 1-h auxin shock 20 or 40 mg I-1, and transferred to hormone- free MS medium). Initiation of autonomous endosperm ( AE) development was induced on all media used in 54 ovules from 39 cultured ovaries ( 26%), with an average frequency of 1.4 ovules/ ovary. The highest frequency of partial endosperm formation occurred on media combining the two growth regulators BAP and NAA ( 59% of ovaries had ovules with AE), although endosperm development was also induced on hormone- free medium ( in 20.5% of ovaries). The number of AE nuclei ranged from 2 to similar to 50, depending on the day of culture and medium; neither cellularization nor differentiation on specific regions typical for endosperm of wild-type Arabidopsis, were noted. Fertilization independent endosperm most probably originated from the secondary nucleus, but involvement of the polar nuclei could not be excluded, as indicated by nuclear size and structure. In vitro conditions did not influence egg cell proliferation. Gynogenic embryos were observed neither in the ovules with autonomous endosperm nuclei nor in ovules without endosperm induction.