Arabidopsis thaliana ABSCISIC ACID INSENSITIVE3 (ABI3) is a transcription factor in the B3 domain family. ABI3, along with B3 domain transcription factors LEAFY COTYLEDON2 (LEC2) and FUSCA3 (FUS3), and LEC1, a subunit of the CCAAT box‐binding complex, form the so‐called LAFL network to control various aspects of seed development and maturation. ABI3 also contributes to the abscisic acid (ABA) response. We report on chromatin immunoprecipitation‐tiling array experiments to map binding sites for ABI3 globally. We also assessed transcriptomes in response to ABI3 by comparing developing abi3‐5 and wild‐type seeds and combined this information to ascertain direct and indirect responsive ABI3 target genes. ABI3 can induce and repress its transcription of target genes directly and some intriguing differences exist in cis motifs between these groups of genes. Directly regulated targets reflect the role of ABI3 in seed maturation, desiccation tolerance, entry into a quiescent state and longevity. Interestingly, ABI3 directly represses a gene encoding a microRNA (MIR160B) that targets AUXIN RESPONSE FACTOR (ARF)10 and ARF16 that are involved in establishment of dormancy. In addition, ABI3, like FUS3, regulates genes encoding MIR156 but while FUS3 only induces genes encoding this product, ABI3 induces these genes during the early stages of seed development, but represses these genes during late development. The interplay between ABI3, the other LAFL genes, and the VP1/ABI3‐LIKE (VAL) genes, which are involved in the transition to seedling development are examined and reveal complex interactions controlling development.

中文翻译：

---

拟南芥种子转录因子ABSCISIC ACID INSENSITIVE 3的直接和间接靶标。

拟南芥ABSCISIC ACID INSENSITIVE3（ABI3）是B3域家族中的转录因子。ABI3与B3域转录因子LEAFY COTYLEDON2（LEC2）和FUSCA3（FUS3）以及CCAAT盒结合复合物的亚基LEC1形成了所谓的LAFL网络，以控制种子发育和成熟的各个方面。ABI3也有助于脱落酸（ABA）的反应。我们报道了染色质免疫沉淀-平铺阵列实验，以绘制全球ABI3的结合位点。我们还通过比较发育中的abi3-5评估了对ABI3的转录组和野生型种子，并结合这些信息来确定直接和间接响应的ABI3目标基因。ABI3可以直接诱导和抑制靶基因的转录，而这些基因组之间的顺式基序存在一些有趣的差异。直接调控的靶标反映了ABI3在种子成熟，耐干燥性，进入静止状态和寿命方面的作用。有趣的是，ABI3直接抑制编码靶向休眠的AUXIN反应因子（ARF）10和ARF16的microRNA（MIR160B）基因。此外，ABI3与FUS3一样，调节编码MIR156的基因但是FUS3仅诱导编码该产物的基因，而ABI3在种子发育的早期诱导这些基因，而在发育后期抑制这些基因。研究了ABI3，其他LAFL基因和VP1 / ABI3-LIKE（VAL）基因之间的相互作用，这些基因参与了幼苗发育的过渡，揭示了控制发育的复杂相互作用。