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A study of polymorphism and species divergence of the dpp gene of Drosophila has been made. Eighteen lines from a population of D. melanogaster were sequenced for 5200 bp of the Hin region of the gene, coding for the dpp polypeptide. A comparison was made with sequence from D. simulans. Ninety-six silent polymorphisms and three amino acid replacement polymorphisms were found. The overall silent polymorphism (0.0247) is low, but haplotype diversity (0.0066 for effectively silent sites and 0.0054 for all sites) is in the range found for enzyme loci. Amino acid variation is absent in the N-terminal signal peptide, the C-terminal TGF-[Beta] peptide and in the N-terminal half of the pro-protein region. At the nucleotide level there is strong conservation in the middle half of the large intron and in the 3[prime] untranslated sequence of the last exon. The 3[prime] untranslated conservation, which is perfect for 110 bp among all the divergent species, is unexplained. There is strong positive linkage disequilibrium among polymorphic sites, with stretches of apparent gene conversion among originally divergent sequences. The population apparently is a migration mixture of divergent clades.

Bright blue or red flowers in the Japanese morning glory (Ipomoea nil) contain anthocyanidin 3-O-sophoroside derivatives, whereas the reddish-brown or purplish-gray petals in itsduskymutants accumulate anthocyanidin 3-O-glucoside derivatives. TheDuskygene was found to encode a novel glucosyltransferase, UDP-glucose:anthocyanidin 3-O-glucoside-2′′-O-glucosyltransferase (3GGT), which mediates the glucosylation of anthocyanidin 3-O-glucosides to yield anthocyanidin 3-O-sophorosides.Ipomoea nilcarries one copy of the3GGTgene that contains no intron and produces 1.6-kbp transcripts mainly in the petals and tubes of flower buds at around 24 h before flower opening. The gene products of bothIn3GGTinI. nilandIp3GGTin the common morning glory (Ipomoea purpurea) comprise 459 amino acids and showed a close relationship to the petunia UDP-rhamnose:anthocyanidin 3-O-glucoside-6′′-O-rhamnosyltransferase (3RT), which controls the addition of a rhamnose molecule to anthocyanidin 3-O-glucosides for conversion into anthocyanidin 3-O-rutinosides. All of the 30duskymutants tested were found to carry the 4-bp insertion mutations GGAT or CGAT at an identical position near the 3′ end of the gene, and the insertions caused frameshift mutations. The expected 3GGT enzymatic activities were found in the crude extracts ofEscherichia coli, in which the3GGTcDNA ofI. nilorI. purpureawas expressed, while no such activity was detected in the extracts expressed with theduskymutant cDNAs containing 4-bp insertions. Moreover, the introducedIp3GGTcDNA efficiently produced 3GGT that converted cyanidin 3-O-glucoside into cyanidin 3-O-sophoroside in transgenic petunia plants. [ABSTRACT FROM AUTHOR]

ANGUSTIFOLIA (AN) is the first C-terminal binding protein (CtBP) gene from plants and controls leaf width and pattern of trichome branching in Arabidopsis thaliana (L.) Heynh. We characterized an ortholog of AN from Ipomoea nil (L.) Roth (Japanese morning glory) and designated it Ipomoea nil’s AN (IAN). IAN is a single-copy gene in the genome and is expressed ubiquitously in various organs of I. nil. IAN contains not only a D2-HDH motif, which is highly conserved within the CtBP family, but also LXCXE, NLS and PEST motifs, which are specific to the AN subfamily. The expression of IAN cDNA driven by the cauliflower mosaic virus 35S promoter restored a defect in leaf expansion in the leaf width direction in the angustifolia-1 (an-1) mutant of Arabidopsis, suggesting that IAN retains a common function with AN. In contrast, the complementation by IAN of a defect in the trichome branching pattern on the leaf surface of the an-1 mutant was less effective than that observed for leaf shape. These results suggest that the mechanisms by which AN regulates leaf width and trichome branching are separable. [ABSTRACT FROM AUTHOR]

The study of AFLP analysis inKandelia obovata, one of the major mangrove species in Japan, revealed the existence of a unique fragment showing stuttered peaks. We cloned this fragment and found a novel microsatellite locus. We report the method used for isolation and the polymorphic nature of this locus among the populations on Iriomote Island. [ABSTRACT FROM AUTHOR]

Although Japanese morning glory (Ipomoea nil (L.) Roth.) has been used intensively for genetic studies, DNA markers have not been developed in Ipomoea nil sufficient to cover all chromosomes. Therefore, we conducted microsatellite (simple sequence repeats, SSR) marker development in I. nil for future genetic studies. From 92,662 expressed sequence tag (EST) sequences, 514 unique microsatellite-containing ESTs were identified. Primer pairs were designed automatically in 326 SSRs. Of 150 SSRs examined, 75 showed polymorphisms among strains. A phenogram based on the SSR genotypes revealed the genetic relation among seven Japanese morning glories from five different regions of the world and an ivyleaf morning glory (I. hederacea Jacq.). The developed SSR markers might be applicable for genetic studies of morning glories and their relatives. [ABSTRACT FROM AUTHOR]