A Silk-Expressed Pectin Methylesterase Confers Cross-Incompatibility Between Wild and Domesticated Strains of Zea mays

Lu, Y.; Hokin, S. A.; Kermicle, J. L.; Evans, M. M. S.

doi:10.1101/529032

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bioRxiv · 10.1101/529032

A Silk-Expressed Pectin Methylesterase Confers Cross-Incompatibility Between Wild and Domesticated Strains of Zea mays

Lu, Y.·Hokin, S. A.·Kermicle, J. L.·Evans, M. M. S.

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Abstract

Despite being members of the same species, some strains of wild teosinte maintain themselves as a distinct breeding population by blocking fertilization by pollen from neighboring maize plants. These teosinte strains may be in the process of evolving into a separate species, since reproductive barriers that block gene flow are critical components in speciation. This trait is conferred by the Teosinte crossing barrier1-s (Tcb1-s) haplotype, making Tcb1 a speciation gene candidate. Tcb1-s contains a female gene that blocks non-self-type pollen and a male function that enables self-type pollen to overcome that block. The Tcb1-female gene encodes a Pectin Methylesterase, implying that modification of the pollen cell wall by the pistil is a key mechanism by which these teosinte females reject foreign (but closely related) pollen. One sentence summaryThe Tcb1-female gene encodes a Pectin Methylesterase that in teosinte silks prevents fertilization by maize pollen.

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Lu, Y., Hokin, S. A., Kermicle, J. L., Evans, M. M. S.. 2019-01-23. A Silk-Expressed Pectin Methylesterase Confers Cross-Incompatibility Between Wild and Domesticated Strains of Zea mays. https://doi.org/10.1101/529032

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