Variation in the fruit development gene POINTED TIP regulates protuberance of tomato fruit tip

Abstract

AbstractThe domestication of tomato has led to striking variations in fruit morphology. Here, we show a genome-wide association study (GWAS) to understand the development of the fruit tip and describe aPOINTED TIP(PT) gene that encodes a C2H2-type zinc finger transcription factor. A single nucleotide polymorphism is found to change a histidine (H) to an arginine (R) in the C2H2 domain of PT and the two alleles are referred to asPTHandPTR. Knocking outPTHleads to development of pointed tip fruit.PTHfunctions to suppress pointed tip formation by downregulating the transcription ofFRUTFULL 2(FUL2), which alters the auxin transport. Our evolutionary analysis and previous studies by others suggest that thePTRallele likely hitch-hiked along with other selected loci during the domestication process. This study uncovers variation inPTand molecular mechanism underlying fruit tip development in tomato.