Promoters are essential regulatory elements for efficiently expressing a gene of interest in a target tissue of a organism. Therefore, the identification of a suitable promoter is important in plant biotechnology. In this study, four promoters were selected and identified to be constitutively or tissue-specifically expressed in Brassica rapa bacterial artificial chromosome (BAC) clones using the results of transcriptomic analysis of Brassica rapa and open-source database information on Arabidopsis thaliana. The 2 kb region of the 5′ upstream was isolated from the Brassica rapa genomic DNA for each promoter. The four promoters were then fused to β-glucuronidase (gus) and green fluorescent protein (gfp) genes, and the recombinant transgenes were introduced into Arabidopsis. As a result of histochemical GUS staining, GFP fluorescence and RT-PCR, the gus gene was observed to be expressed constitutively in all tissues using all four promoters. A GUS activity assay using fluorescent 4-MUG revealed that the BR11 promoter showed similar activity to the CaMV35S promoter, while the BR4, BR15, and BR16 promoters showed 1.5, 4, and 18-fold higher activities than the CaMV35S promoter, respectively. These results indicate that these four promoters could be used to incorporate useful genes with enhanced function into crops of interest.

To identify and apply tissue-specific promoters is one of the major challenges in plants genetic engineering for optimizing efficient expression of interest genes in appropriate tissues. In this research, open-source database information of Arabidopsis thaliana was adapted to determine root-specific expressed promoter region. A total seven sequences that might function as a root-specific promoter element were initially isolated from Arabidopsis genomic DNA. Then seven promoters were cloned into pBGWFS7 in which β-glucuronidase (gus) and green fluorescent protein (gfp) genes were linked. The GUS activities were measured in different tissues of transgenic Arabidopsis by both histochemical GUS staining and fluorescent 4 methylumbelliferyl β-D-glucuronide (MUG) assay. To confirm root-specific expression, GFP-confocal microscope analysis was conducted in Arabidopsis transgenic plant. As a result, the five promoters showed strong GUS activity in the root tissue as compared with the CaMV35S promoter. To test crop application availability as a root-specific promoter, seven promoters were introduced into tomato plants and confirmed transient expression using Agrobacterium rhizogenesis ARqua1 root-nodule inducible strain. Two promoters showed that gus genes were specifically expressed in roots of transgenic tomato plant. Taken together, the novel seven promoters showed specific activity in root suggesting that it is applicable in crop improvement.

The ω5-gliadins are the major allergens in wheat-dependent excise-induced anaphylaxis (WDEIA). In this study, SDS-PAGE analysis was used to assign the ω5-gliadins (Gli-B1) alleles in thirty two Korean wheat cultivars, compared with eleven standard wheat cultivars for Gli-B1a~m alleles. These results were reconfirmed with their complementary Glu-B3 low-molecular-weight glutenin subunits alleles tightly linked with Gli-B1 locus revealed with 2-DGE in our previous study. As a result, one Gli-B1b, four Gli-B1d, two Gli-B1f, six Gli-B1m and nineteen Gli-B1h varieties were identified. This is the first report on revealing the Gli-B1 alleles in Korean wheat cultivars and represents valuable basic data on wheat allergy, relationship between gliadin and wheat quality, and development of hypo-allergenic wheat.

Low-molecular-weight glutenin subunits (LMW-GS) play a crucial role in the processing quality of wheat flour. They are encoded multi gene family located at the Glu-A3, Glu-B3 and Glu-D3 on the short arm of chromosome 1A, 1B and 1D respectively. Typical LMW-GSs are composed of three parts including a short N-terminal domain, a relatively short repetitive domain and a C-terminal domain. Further, typical LMW-GS sequences are divided into LMW-s, LMW-m and LMW-i types, on the basis of the first amino acid of the mature proteins (serine, methionine and isoleucine, respectively). Although it is known that the allelic variation of LMW-GSs affect the properties of dough, it is still not clear which LMW-GSs confer better bread-making quality because of the larger number of expressed subunits and their overlapping mobility with abundant gliadin proteins. Therefore, it is important to characterize LMW-GS genes and develop functional markers to identify different LMW-GS alleles for application in wheat breeding. In this review, we discuss the various aspects of LMW-GS, including their structural characteristics, the development of marker, relationship between LMW-GSs and bread wheat quality, and genetic engineering of the LMW-GSs.

Geonyangmi, low glutelins rice cultivar, was developed by the rice breeding team of National Institute of Crop Science (NICS), RDA in 2011. This cultivar was derived from the cross between Jinmi TR and LGC-1 in 2003 summer season, and selected by a promising line, SR29355-B-51-2-2-1, was selected and designated as the line of Suweon533 in 2009. The local adaptability test of Suweon533 was carried out at three locations from 2009 to 2011 and it was named as Geonyangmi. This variety is a mid-late maturity cultivar. This variety has 90 cm in culm length and 124 spikelets per panicle. Its 1,000 grain-weight of brown rice is 19.3 g which is less than that of Hwaseonbyeo. This variety has tolerance to unfavorable environment such as cold. This variety has translucent and clear milled rice kernel without white core and belly rice. It has low glutelin content compared with Jinmibyeo. This variety is susceptible to leaf blast, bacterial blight, virus disease and insect pest. The yield potential of Geonyangmi was about 4.93 MT/ha at ordinary fertilizer level in local adaptability test for three years. This variety would be adaptable to the plain paddy field of middle of Korea.