Polyamines and transglutaminase activity are involved in compatible and self-incompatible pollination of Citrus grandis
Polyamines and transglutaminase activity are involved in compatible and self-incompatible pollination of Citrus grandis
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DOI：
10.1007/s00726-011-1017-9
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发表时间：
2012-02-01
期刊：
影响因子：
3.5
通讯作者：
Del Duca, Stefano
中科院分区：
文献类型：
--
作者：
Gentile, Alessandra;Antognoni, Fabiana;Del Duca, Stefano
利用柱头表面添加亲和性和自交不亲和性(SI)花粉的方法，对蜜柚雌蕊的授粉进行了研究。在荧光显微镜下观察到雌蕊内的花粉萌发，结果表明，雌蕊的形态发生了变化，管壁中有不规则的老茧沉积，增大的顶端有大量的老茧沉积。分析了多胺(PA)作为游离、高氯酸(PCA)可溶和不溶部分的含量和转谷氨酰胺酶(TGase)活性，以加深它们可能参与植物生殖的孕育期。在亲和授粉和SI授粉的雌蕊中，PCA可溶部分中的共轭多胺含量明显高于游离和不溶于PCA的形式。在雌蕊中，授粉引起游离Pa的早期减少和结合形式的增加。SI授粉时，可溶于和不溶于PCA的PAS值最高，最大值伴随着花粉管停滞。由于TGase通过将PAS与蛋白质共价结合来调节它们的一些效应，它的活性以前从未在柑橘中被检查过，因此用两种不同的方法进行了检测。此外，谷氨酰-PAS的存在证实了酶分析数据，并排除了误解的可能性。SI授粉引起TGase活性升高，亲和授粉导致TGase活性下降。与结合的Pas类似，在SI授粉的雌蕊中，谷氨酰-Pas和酶活性达到峰值，并伴随着观察到的花粉管生长受阻，这表明TGase参与了SI的反应。
Pollination of pummelo (Citrus grandis L. Osbeck) pistils has been studied in planta by adding compatible and self-incompatible (SI) pollen to the stigma surface. The pollen germination has been monitored inside the pistil by fluorescent microscopy showing SI altered morphologies with irregular depositions of callose in the tube walls, and heavy callose depositions in enlarged tips. The polyamine (PA) content as free, perchloric acid (PCA)-soluble and -insoluble fractions and transglutaminase (TGase) activity have been analyzed in order to deepen their possible involvement in the progamic phase of plant reproduction. The conjugated PAs in PCA-soluble fraction were definitely higher than the free and the PCA-insoluble forms, in both compatible and SI pollinated pistils. In pistils, pollination caused an early decrease of free PAs and increase of the bound forms. The SI pollination, showed highest values of PCA-soluble and -insoluble PAs with a maximum in concomitance with the pollen tube arrest. As TGase mediates some of the effects of PAs by covalently binding them to proteins, its activity, never checked before in Citrus, was examined with two different assays. In addition, the presence of glutamyl-PAs confirmed the enzyme assay data and excluded the possibility of a misinterpretation. The SI pollination caused an increase in TGase activity, whereas the compatible pollination caused its decrease. Similarly to bound PAs, the glutamyl-PAs and the enzyme activity peaked in the SI pollinated pistils in concomitance with the observed block of the pollen tube growth, suggesting an involvement of TGase in SI response.