Two GLOBOSA-like genes are expressed in second and third whorls of homochlamydeous flowers in Asparagus officinalis L.
Garden asparagus (Asparagus officinalis L.) has homochlamydeous flowers. Like Liliaceae plants such as lily and tulip, the perianths of asparagus have two whorls of almost identical petaloid organs, called tepals. Floral structures of these homochlamydeous flowers could be explained by a modified ABC model, in which the expression of the class B genes has expanded to whorl 1, so that the organs of whorls 1 and 2 have the same petaloid structure. In this study, we isolated and characterized two GLOBOSA-like genes (AOGLOA and AOGLOB), one of class B gene, from asparagus. Southern blot showed that AOGLOA and AOGLOB genes are single copy genes. Northern blot analysis indicated that these genes were specifically expressed in male and female flowers. In situ hybridization showed that the expression of AOGLOA and AOGLOB genes is confined to whorls 2 and 3 (inner tepal and stamen) and not detected in whorl 1 (outer tepal). The other asparagus class B gene, AODEF, was also not expressed in outer tepal [Park et al. (2003) Plant Mol Biol. 51: 867]. These results indicate that the class B genes are not involved in the outer tepal development in asparagus, not supporting the modified ABC model in asparagus.
Park
Jin-Heui
JH
Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577 Japan.
Ishikawa
Yuichi
Y
Ochiai
Toshinori
T
Kanno
Akira
A
Kameya
Toshiaki
T
D000595:Amino Acid Sequence; D027761:Asparagus Plant / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D015152:Blotting, Northern; D015139:Blotting, Southern; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D035264:Flowers / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics*; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D018076:DNA, Complementary; D018744:DNA, Plant; C102172:GLOBOSA protein, plant; D018398:Homeodomain Proteins; D010940:Plant Proteins; D012333:RNA, Messenger