Vardanega Isaia, Maika Jan Eric, Demesa-Arevalo Edgar, Lan Tianyu, Kirschner Gwendolyn K, Imani Jafargholi, Acosta Ivan F, Makowska Katarzyna, Hensel Götz, Ranaweera Thilanka, Shiu Shin-Han, Schnurbusch Thorsten, von Korff Maria, Simon Rüdiger
Institute of Developmental Genetics, Heinrich-Heine University, Düsseldorf, Germany.
CEPLAS, Center of Excellence in Plant Sciences, Heinrich-Heine University, Düsseldorf, Germany.
Nat Commun. 2025 Apr 26;16(1):3937. doi: 10.1038/s41467-025-59330-z.
The large variety of inflorescence architectures evolved in grasses depends on shape, longevity and determinacy of meristems directing growth of the main and lateral axes. The CLAVATA pathway is known to regulate meristem size and inflorescence architecture in grasses. However, how individual meristem activities are determined and integrated to generate specific inflorescences is not yet understood. We found that activity of distinct meristems in the barley inflorescence is controlled by a signalling pathway comprising the receptor-like kinase Hordeum vulgare CLAVATA1 (HvCLV1) and the secreted CLAVATA3/EMBRYO-SURROUNDING REGION RELATED (CLE)-family peptide FON2-LIKE CLE PROTEIN1 (HvFCP1). HvFCP1 and HvCLV1 interact to promote spikelet formation, but restrict inflorescence meristem and rachilla proliferation. Hvfcp1 or Hvclv1 mutants generate additional rows of spikelets and supernumerary florets from extended rachilla activity. HvFCP1/HvCLV1 signalling coordinates meristem activity through regulation of trehalose-6-phosphate levels. Our discoveries outline a path to engineer inflorescence architecture via specific regulation of distinct meristem activities.
禾本科植物中进化出的多种多样的花序结构取决于主导主轴和侧轴生长的分生组织的形状、寿命和确定性。已知CLAVATA途径可调节禾本科植物的分生组织大小和花序结构。然而，目前尚不清楚各个分生组织的活动是如何被确定和整合以产生特定花序的。我们发现，大麦花序中不同分生组织的活动受一个信号通路控制，该信号通路由类受体激酶大麦CLAVATA1（HvCLV1）和分泌的CLAVATA3/胚周围区域相关（CLE）家族肽FON2-LIKE CLE蛋白1（HvFCP1）组成。HvFCP1和HvCLV1相互作用以促进小穗形成，但限制花序分生组织和小穗轴的增殖。HvFCP1或HvCLV1突变体通过延长的小穗轴活动产生额外的小穗行和多余的小花。HvFCP1/HvCLV1信号通路通过调节海藻糖-6-磷酸水平来协调分生组织活动。我们的发现勾勒出了一条通过对不同分生组织活动进行特定调控来设计花序结构的途径。
