Kong Lisheng, von Aderkas Patrick
Centre for Forest Biology, Department of Biology, University of Victoria, 3800 Finnerty Rd, Victoria, BC, Canada V8W 3N5.
J Exp Bot. 2007;58(6):1525-31. doi: 10.1093/jxb/erm019. Epub 2007 Feb 28.
Abscisic acid (ABA) plays an important role during somatic embryo development and maturation in coniferous species. The purpose of this research was to study ABA utilization by genotypes with different embryo maturation capabilities in interior spruce. Cell lines ISP11 and ISP48 were of high embryo maturation capability. By contrast, the tissue of line ISP16 contained numerous immature embryos, but only a few mature embryos developed. Exogenous ABA, i.e. S-ABA [(+)-cis, trans-ABA], racemic ABA, or ABA isomers were added into suspension cultures at a final concentration of 30 microM. In comparison to racemic ABA and ABA isomers, S-ABA reduced tissue proliferation the most. In all cell lines, about half of the racemic ABA was used within 2 weeks; the remaining ABA was (-)-cis, trans-ABA. The concentration of ABA showed little change thereafter. In the cultures supplied with ABA isomers, about half of (+/-)-cis, trans-ABA was utilized during 22 d. By contrast, (+/-)-trans, trans-ABA was hardly used, especially in line ISP16. S-ABA was almost completely metabolized by line ISP11. However, approximately 28% and 22% of the S-ABA remained in the culture of cell lines ISP16 and ISP48, respectively. Cell line ISP16 grew the fastest in culture. By 3 weeks, S-ABA consumption by ISP11 and ISP48 on the basis of tissue growth was, respectively, 2.2-fold and 3.4-fold greater than that of ISP16. A higher ratio of dihydrophaseic acid to phaseic acid existed with cell lines of higher embryo maturation capability, especially when the exogenously supplied ABA was chemically synthesized.
脱落酸（ABA）在针叶树种的体细胞胚胎发育和成熟过程中起着重要作用。本研究的目的是研究内部云杉中具有不同胚胎成熟能力的基因型对ABA的利用情况。细胞系ISP11和ISP48具有较高的胚胎成熟能力。相比之下，ISP16系的组织含有大量未成熟胚胎，但只有少数成熟胚胎发育。将外源ABA，即S-ABA[（+）-顺，反式ABA]、外消旋ABA或ABA异构体以终浓度30 microM添加到悬浮培养物中。与外消旋ABA和ABA异构体相比，S-ABA对组织增殖的抑制作用最大。在所有细胞系中，约一半的外消旋ABA在2周内被利用；其余的ABA是（-）-顺，反式ABA。此后ABA浓度变化不大。在供应ABA异构体的培养物中，约一半的（±）-顺，反式ABA在22天内被利用。相比之下，（±）-反，反式ABA几乎未被利用，尤其是在ISP16系中。S-ABA几乎被ISP11系完全代谢。然而，分别约有28%和22%的S-ABA保留在细胞系ISP16和ISP48的培养物中。细胞系ISP16在培养中生长最快。到3周时，基于组织生长，ISP11和ISP48对S-ABA的消耗分别比ISP16高2.2倍和3.4倍。胚胎成熟能力较高的细胞系中，二氢phaseic酸与phaseic酸的比例更高，尤其是当外源供应的ABA是化学合成的时候。
