• Exogenous application of CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION (CLE) peptides suppresses protophloem differentiation and leads to the consumption of the proximal root meristem. However, the exact CLE peptides and the corresponding receptor complex regulating protophloem differentiation have not yet been clarified.
• Through expression pattern and phylogenetic analyses, CLE25/26/45 were identified as candidate peptides. Further genetic analyses, physiological assays and specific protophloem marker observations indicated that CLE25/26/45, BARELY ANY MERISTEM1/3 (BAM1/3) and CLV3 INSENSITIVE KINASEs (CIKs) are involved in regulating protophloem differentiation.
• The cle25 26 45 and cik2 3 4 5 6 mutation can greatly rescue the root defects of brevis radix (brx) and octopus (ops) mutants. The protophloem differentiation and proximal root meristem consumption of clv1 bam1 3 and cik2 3 4 5 6 were insensitive to CLE25/26/45 treatments. cle25 26 45, clv1 bam1 3 and cik2 3 4 5 6 displayed similar premature protophloem. In addition, CLE25/26/45 induced the interactions between BAMs and CIKs in vivo. Furthermore, CLE25/26/45 enhanced the phosphorylation levels of CIKs, which were greatly impaired in clv1 bam1 3 mutant.
• Our work clarifies that the CLE25/26/45–BAM1/3–CIK2/3/4/5/6 signalling module genetically acts downstream of BRX and OPS to suppress protophloem differentiation.

中文翻译：

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一个 CLE-BAM-CIK 信号模块控制拟南芥根原韧皮部的分化

• CLAVATA3 (CLV3)/EMBRYO SURROUNDING REGION (CLE) 肽的外源应用抑制原韧皮部分化并导致近端根分生组织的消耗。然而，确切的 CLE 肽和相应的调节原韧皮部分化的受体复合物尚未阐明。
• 通过表达模式和系统发育分析，CLE25/26/45 被确定为候选肽。进一步的遗传分析、生理分析和特定的原韧皮部标记观察表明，CLE25/26/45、几乎没有任何 MERISTEM1/3 (BAM1/3) 和 CLV3 不敏感激酶 (CIK) 参与调节原韧皮部分化。
• cle25 26 45和cik2 3 4 5 6突变可以极大地挽救短尾( brx )和章鱼( ops )突变体的根缺陷。clv1 bam1 3和cik2 3 4 5 6的原韧皮部分化和近根分生组织消耗对CLE25/26/45处理不敏感。cle25 26 45、clv1 bam1 3和cik2 3 4 5 6显示出相似的过早原韧皮部。此外，CLE25/26/45在体内诱导 BAMs 和 CIKs 之间的相互作用. 此外，CLE25/26/45 增强了 CIK 的磷酸化水平，这在clv1 bam1 3突变体中大大受损。
• 我们的工作阐明了 CLE25/26/45–BAM1/3–CIK2/3/4/5/6 信号模块在遗传上作用于 BRX 和 OPS 的下游以抑制原韧皮部分化。