Asante Daniel K A, Yakovlev Igor A, Fossdal Carl Gunnar, Timmerhaus Gerrit, Partanen Jouni, Johnsen Oystein
Department of Biology, University of Tromsø, N-9037 Tromsø, Norway.
Plant Physiol Biochem. 2009 Aug;47(8):681-9. doi: 10.1016/j.plaphy.2009.03.004. Epub 2009 Mar 24.
Expression of selected genes in needles of Norway spruce (Picea abies [L.] Karst) was investigated by following their transcription levels during late autumn. Transcription was assessed in mature needles which likely serve as sensor of environmental cues that enable trees in the temperate and boreal regions to change between stages of growth, frost tolerance and bud dormancy. Samples were collected from grafts kept under outdoor conditions and after bud burst forcing in greenhouse at 20 degrees C (12 h darkness) for one week. Transcription was assayed with real-time RT-PCR. During the sampling period, chilling requirement was partially fulfilled, and time to bud burst after forcing was decreased. Of the 27 transcripts studied, expression of 16 was significantly affected either by forcing, sampling time, or interaction between them. PaSAP, PaACP, PaSGS3, PaWRKY, PaDIR9, PaCCCH and dehydrin genes responded drastically to forcing temperatures at all sampling points, showing no correlation with readiness for bud burst. Expression patterns of some vernalization pathway gene homologs PaVIN3, and also of PaMDC, PaLOV1 and PaDAL3 had a clear opposite trends between forcing and outdoor conditions, which could imply their role in chilling accumulation and bud burst regulation/cold acclimation. These genes could constitute putative candidates for further detailed study, whose regulation in needles may be involved in preparation towards bud burst and chilling accumulation sensing.
通过跟踪挪威云杉（Picea abies [L.] Karst）针叶中选定基因在深秋期间的转录水平，对其表达情况进行了研究。在成熟针叶中评估转录情况，这些针叶可能充当环境线索的传感器，使温带和寒带地区的树木能够在生长、抗冻性和芽休眠阶段之间转变。样本取自室外条件下保存的嫁接苗，以及在20摄氏度（12小时黑暗）的温室中进行催芽处理一周后的样本。采用实时逆转录聚合酶链反应（RT-PCR）检测转录情况。在采样期间，部分满足了低温需求，催芽后芽萌发的时间缩短。在所研究的27种转录本中，16种的表达受到催芽处理、采样时间或二者相互作用的显著影响。在所有采样点，挪威云杉衰老相关蛋白（PaSAP）、酸性磷酸酶（PaACP）、拟南芥沉默基因3（PaSGS3）、WRKY转录因子（PaWRKY）、DIR9基因、锌指蛋白基因（PaCCCH）和脱水素基因对催芽温度反应剧烈，与芽萌发准备情况无相关性。一些春化途径基因同源物PaVIN3以及PaMDC、蓝光受体1（PaLOV1）和DAL3基因的表达模式在催芽处理和室外条件下呈现明显相反的趋势，这可能暗示它们在低温积累以及芽萌发调控/冷驯化中的作用。这些基因可能是进一步详细研究的推定候选基因，它们在针叶中的调控可能参与芽萌发准备和低温积累感知。
