气候变化正在急剧增加世界各地盐渍土壤的总面积,每年增加约200万公顷。土壤盐分降低作物产量,因此,使农业利润降低,可能导致许多地区贫困和饥饿加剧。该问题的解决方案是提高作物的耐盐性。作物植物内的转录因子(TFs)代表了理解耐盐性的关键。因为这些蛋白质在与盐胁迫相关的功能基因的调节中起着重要作用。碱性亮氨酸拉链(bZIP)TF在调节耐盐性方面具有有据可查的作用。为了更好地理解bZIPTFs与耐盐性的关系,我们使用中国春小麦基因组对小麦进行了全基因组分析,由国际小麦基因组测序协会组装。我们鉴定出89个额外的bZIP基因序列,这使得小麦中的bZIP基因序列总数达到237。这237个序列中的大多数包含一个bZIP蛋白结构域;然而,也存在其他五个域的不同组合。bZIP蛋白分为10个亚家族组。使用计算机模拟分析,我们鉴定了5个参与调节盐胁迫的bZIP基因(ABF2,ABF4,ABI5,EMBP1和VIP1).通过仔细检查与2000bp上游区域的结合特性,我们确定了受这些TFs调控的推定功能基因。用或不用100mMNaCl处理的植物组织的表达分析揭示了TF和功能基因之间的可变模式。例如,ABF4的表达增加与根和芽组织中相应功能基因的表达增加相关,而根组织中的VIP1下调强烈降低了两个功能基因的表达。确定维持本研究中描述的功能基因表达的策略可以增强小麦的耐盐性。
Climate change is dramatically increasing the overall area of saline soils around the world, which is increasing by approximately two million hectares each year. Soil salinity decreases crop yields and, thereby, makes farming less profitable, potentially causing increased poverty and hunger in many areas. A solution to this problem is increasing the salt tolerance of crop plants. Transcription factors (TFs) within crop plants represent a key to understanding salt tolerance, as these proteins play important roles in the regulation of functional genes linked to salt stress. The basic leucine zipper (
bZIP) TF has a well-documented role in the regulation of salt tolerance. To better understand how
bZIP TFs are linked to salt tolerance, we performed a genome-wide analysis in wheat using the Chinese spring wheat genome, which has been assembled by the International Wheat Genome Sequencing Consortium. We identified 89 additional
bZIP gene sequences, which brings the total of
bZIP gene sequences in wheat to 237. The majority of these 237 sequences included a single bZIP protein domain; however, different combinations of five other domains also exist. The
bZIP proteins are divided into ten subfamily groups. Using an in silico analysis, we identified five
bZIP genes (ABF2, ABF4, ABI5, EMBP1, and VIP1) that were involved in regulating salt stress. By scrutinizing the binding properties to the 2000 bp upstream region, we identified putative functional genes under the regulation of these TFs. Expression analyses of plant tissue that had been treated with or without 100 mM NaCl revealed variable patterns between the TFs and functional genes. For example, an increased expression of ABF4 was correlated with an increased expression of the corresponding functional genes in both root and shoot tissues, whereas VIP1 downregulation in root tissues strongly decreased the expression of two functional genes. Identifying strategies to sustain the expression of the functional genes described in this study could enhance wheat\'s salt tolerance.