Microtubule-associated proteins regulate tomato fruit shape
Bao et al. reveal how microtubule-associated proteins regulate tomato fruit shape formation from a cell biology perspective.
Plant Cell https://doi.org/10.1093/plcell/koad231
Zhiru Bao and Pengwei Wang
National Key Laboratory for Germplasm Innovation & Utilization of Horticultural Crops, College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan 430070, Hubei Province, China; 2. Hubei Hongshan Laboratory, Wuhan 430070, China
Background: Genes encoding microtubule-binding proteins have emerged as conserved trait loci for fruit shape regulation with important roles during domestication. While microtubule-binding proteins have been reported in many fruit crops, most studies were performed using forward genetics or population genetics approaches. Thus, in-depth molecular and cell biology insight is lacking.
Question: How are cortical microtubules organized in fruit tissue? From a cell biology perspective, which proteins regulate microtubule dynamics and organization in tomato fruits?
Findings: We identified the microtubule-associated proteins SlMAP70s and SlIQD21a as important regulators of tomato fruit shape. These proteins interact and affect microtubule stability, which may contribute to the re-arrangement of cortical microtubules and cell growth patterns underlying organ shape. Transgenic tomato lines over-expressing SlMAP70-1 produced elongated fruits with reduced cell circularity and microtubule anisotropy, while loss-of-function mutants exhibited flatter fruits. Fruits were further elongated in plants co-expressing both SlMAP70-1 and SlIQD21a.
Next steps: These findings shed light on the functional regulation of microtubule organization and provide a powerful approach for future studies on fruit shape regulation in fruit crops.
Reference:
Zhiru Bao, Ye Guo, Yaling Deng, Jingze Zang, Junhong Zhang, Yingtian Deng, Bo Ouyang, Xiaolu Qu, Katharina Bürstenbinder and Pengwei Wang. (2023) Microtubule-associated protein SlMAP70 interacts with IQ67-domain protein SlIQD21a to regulate fruit shape in tomato. https://doi.org/10.1093/plcell/koad231
