Tomato fruit color, which is the most visible characteristic among the other fruit traits, is considered to have a substantial influence on consumers. The pink-colored tomatoes with high soluble solids content are considerably preferred especially in Asia compared to the other colors. Generally the pink fruit trait of tomatoes is easily determined by visual examination of intact fruit, however, it is technically determined by the characteristic of the fruit peel. The pink trait is regulated by variations of the SlMYB12(y) gene located on chromosome 1, which controls the accumulation of the naringenin chalcone, which comprises a large proportion of flavonoids. In this study, we developed a derived Cleaved Amplified Polymorphic Sequences (dCAPS) marker and a sequence characterized amplified regions (SCAR) marker in order to discriminate of pink/non-pinktomatoes in the domestic breeding lines. Quantitative RT-PCR analysis indicated that the SlMYB gene is highly expressed in non-pink fruit peel, whereas the expression is significantly lowered in the pink fruit peel. These gene based markers are expected to enhance the efficiency and accuracy of selection pink-tomatoes in tomato breeding programs.

Fresh market tomato cultivars are divided largely based on fruit color appearance (red or pink), which is attributed by the trait of peel. It had been reported that mutation of the Slmyb12 gene suppresses synthesis of yellow-colored flavonoid (naringenin chalcone) in peel and causes pinkish tomato fruit. Whereas wild-type tomato plants synthesizing naringenin chalcone produce yellow-colored peel, which resulting in the fruit appearance to be red. The present study was performed to investigate the association between the Slmyb12 and fruit color of domestic tomato inbreed lines. A SCAR marker was developed from an Indel mutation site (72bp insertion in exon3) of the Slmyb12, and tested on 22 and 18 red and pink-fruited inbred lines, respectively. Unexpectedly, the results showed that all inbred lines tested had wild-type Slmyb12. The full length sequences of the Slmyb12 were cloned from two inbred lines (FCR1 and FCP1), but the sequence alignment did not identify any nucleotide variations within this gene. Furthermore, scanning of SNPs between FCR1 and FCP1 using SolCAP Tomato SNP array) found no SNPs for Slmyb12. To delimit the genomic region of the gene conferring fruit color of domestic tomato lines, we are analyzing SNPs in the genes adjacent to the Slmyb12 using an F2 population derived from FCR1 x FCP1. So far, one SNP located at 1,750kbp downstream from the stop codon of Slmyb12 was mapped using 54 F2 plants and 83% of phenotype-marker association was revealed, demonstrating that the fruit color is controlled bySlmyb12 indeed, or other neighboring gene(s) involved in the pathway of naringenin chalcone synthesis. Further study with more SNPs will clear up this question.

본 연구센터에서는 백색과 황색의 기존 품종의 감자보다 anthocyanin함량이 높고 생리활성이 우수한 것으로 확인된 신품종인 컬러감자 '홍영'과 '자영'을 개발하였으며, 차후 컬러감자를 산업화 용도로 가공 시 전량 폐기되는 외피의 활용도를 높이기 위하여 다음과 같은 생리활성 연구를 실시하였다. 컬러감자외피의 추출물과 분획물을 이용하여 항염증 효과를 검토한 결과, 대식세포인 RAW264.7 cell에서 염증매개물질인 lipopoly sacchride(LPS)로 염증을 유발시켜 nitric oxide(NO), prostagland-in E2(PGE2) inducible nitric oxide synthase(iNOS), 그리고 cyclo oxygenase-2(COX-2)같은 염증유발인자들의 억제효과를 확인하였다. 자색감자인 자영외피 Chloroform분획물의 염증유발인자 억제 시 IC50 value를 측정하여 25~50μg/ml의 농도에서 유의성 있는 항염증 효과를 보였다. Nitric oxide 생성을 농도의존적으로 현저하게 저해하는 농도는 36.15μg/ml이며, 세포독성이 없는 최고 농도인 100μg/ml의 농도에서 LPS에 의해 유도된 PGE2를 76.68%만큼 유의성 있는 저해 효과를 보였다. 그리고 iNOS와 COX-2단백질을 유의성 있게 저해하는 농도는 50μg/ml 처리였으며, 특이적으로 iNOS는 25μg/ml을 처리하였을 때부터 유의성 있는 저해효과를 보였다. 따라서 본 연구 결과는 자영외피의 chloroform 분획물이 유의성 있는 항염증 효과를 나타내며, 이러한 효능은 예방의학적 기능성을 충분이 가지고 있기에 염증성질환의 예방을 위한 건강기능성식품의 개발가능성을 제시할 수 있을 것으로 사료된다.