SPOROCYTELESS/NOZZLE acts together with MADS-domain transcription factors to regulate an auxin-dependent network controlling the Megaspore Mother Cell development

Cavalleri, A.; Astori, C.; Manrique, S.; Bruzzaniti, G.; Smaczniak, C.; Mizzotti, C.; Ruiu, A.; Spano, M.; Movilli, A.; Gregis, V.; Xu, X.; Kaufmann, K.; Colombo, L.

doi:10.1101/2025.03.11.641985

bioRxiv · 10.1101/2025.03.11.641985

SPOROCYTELESS/NOZZLE acts together with MADS-domain transcription factors to regulate an auxin-dependent network controlling the Megaspore Mother Cell development

Cavalleri, A.·Astori, C.·Manrique, S.·Bruzzaniti, G.·Smaczniak, C.·Mizzotti, C.·Ruiu, A.·Spano, M.·Movilli, A.·Gregis, V.·Xu, X.·Kaufmann, K.·Colombo, L.

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Abstract

The formation of the female gamete is a complex developmental process that begins with the differentiation of the Megaspore Mother Cell (MMC) within the ovule. SPOROCYTELESS/NOZZLE (SPL/NZZ) is the principal regulator of the MMC formation, as mutations in the SPL/NZZ gene lead to the failure of the MMC differentiation. Nonetheless, the SPL/NZZ-dependent regulatory pathway governing the MMC development remains largely unknown. Using a multi-omics approach, we identify direct SPL/NZZ targets and their downstream network. We discovered that SPL/NZZ interacts with ovule-identity MADS-domain transcription factor complexes, to regulate the expression of common target genes. By integrating the omics data with the analysis of either complementation or mutant lines, we describe a comprehensive regulatory mechanism, in which SPL/NZZ determines the differentiation of the MMC by acting on an auxin-dependent downstream network.

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Cavalleri, A., Astori, C., Manrique, S., Bruzzaniti, G., Smaczniak, C., Mizzotti, C., Ruiu, A., Spano, M., Movilli, A., Gregis, V., Xu, X., Kaufmann, K., Colombo, L.. 2025-03-13. SPOROCYTELESS/NOZZLE acts together with MADS-domain transcription factors to regulate an auxin-dependent network controlling the Megaspore Mother Cell development. https://doi.org/10.1101/2025.03.11.641985

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