mildew resistance locus o
{{Short description|Plant-specific gene family}}
Mildew locus o (MLO) is a plant-specific gene family. Specific members of the Mildew Locus O gene family act as powdery mildew susceptibility factors. Their inactivation, as the result of a loss-of-function mutation, gene knock-out, or knock-down, is associated with a peculiar form of resistance, referred to as mlo resistance.{{cite web|url=https://www.pomics.com/wang_7_2_2014_87_93.pdf|title=Genome-wide analysis of the mildew resistance locus o (MLO) gene family in tomato (Solanum lycopersicum L.)|publisher=Plant Omics Journal|accessdate=2020-10-19}} {{cite journal|title=Structure, evolution and functional inference on the Mildew Locus O (MLO) gene family in three cultivated Cucurbitaceae spp.|year=2015 |journal=BMC Genomics|doi=10.1186/s12864-015-2325-3 |last1=Iovieno |first1=Paolo |last2=Andolfo |first2=Giuseppe |last3=Schiavulli |first3=Adalgisa |last4=Catalano |first4=Domenico |last5=Ricciardi |first5=Luigi |last6=Frusciante |first6=Luigi |last7=Ercolano |first7=Maria Raffaella |last8=Pavan |first8=Stefano |volume=16 |page=1112 |pmid=26715041 |pmc=4696115 |doi-access=free }} The mlo gene family is widely conserved across the plant kingdom with some members evolving as early as the first land plants.{{cite journal |last1=Kusch |first1=Stefan |last2=Pesch |first2=Lina |last3=Panstruga |first3=Ralph |title=Comprehensive Phylogenetic Analysis Sheds Light on the Diversity and Origin of the MLO Family of Integral Membrane Proteins |journal=Genome Biology and Evolution |year=2016 |volume=8 |issue=3 |pages=878–895 |doi=10.1093/gbe/evw036 |pmid=26893454 |pmc=4824068 |url=https://academic.oup.com/gbe/article/8/3/878/2574141 |access-date=11 January 2021|doi-access=free }} Mlo proteins contain seven highly conserved transmembrane domains, as well as a calmodulin-binding domain. TaMLO genes are the MLOs in bread wheat, Triticum aestivum.{{cite journal | last1=Li | first1=Shaoya | last2=Zhang | first2=Chen | last3=Li | first3=Jingying | last4=Yan | first4=Lei | last5=Wang | first5=Ning | last6=Xia | first6=Lanqin | title=Present and future prospects for wheat improvement through genome editing and advanced technologies | journal=Plant Communications | publisher=CAS Center for Excellence in Molecular Plant Sciences + Chinese Society for Plant Biology (Cell Press) | volume=2 | issue=4 | year=2021 | issn=2590-3462 | doi=10.1016/j.xplc.2021.100211 | page=100211| pmid=34327324 | pmc=8299080 }}