1. An aquaglyceroporin is abundantly expressed early in the development of the suspensor and the embryo proper of loblolly pine.
- Author
-
Ciavatta VT, Morillon R, Pullman GS, Chrispeels MJ, and Cairney J
- Subjects
- Amino Acid Sequence, Animals, Aquaporins metabolism, Cloning, Molecular, Eukaryotic Initiation Factor-3, Female, Fungal Proteins genetics, Gene Expression Regulation, Developmental, Gene Expression Regulation, Plant, Glycerol metabolism, Immediate-Early Proteins genetics, Ion Channels genetics, Membrane Proteins genetics, Molecular Sequence Data, Nuclear Proteins genetics, Oocytes, Osmotic Pressure, Pinus growth & development, Pinus taeda, Plant Proteins genetics, RNA, Messenger genetics, RNA, Messenger metabolism, Saccharomyces cerevisiae genetics, Seeds growth & development, Sequence Homology, Amino Acid, Serine Endopeptidases genetics, Xenopus laevis genetics, Aquaporins genetics, Phylogeny, Pinus genetics, Saccharomyces cerevisiae Proteins, Seeds genetics
- Abstract
In contrast to angiosperms, pines and other gymnosperms form well-developed suspensors in somatic embryogenic cultures. This creates a useful system to study suspensor biology. In a study of gene expression during the early stages of conifer embryogenesis, we identified a transcript, PtNIP1;1, that is abundant in immature loblolly pine (Pinus taeda) zygotic and somatic embryos, but is undetectable in later-stage embryos, megagametophytes, and roots, stems, and needles from 1 year-old seedlings. Analysis of PtNIP1;1 transcript in embryo proper and suspensor tissues by reverse transcription-polymerase chain reaction suggests preferential expression in the suspensor. Based on comparisons of derived amino acid sequences, PtNIP1;1 belongs to the nodulin-like members of the major intrinsic protein superfamily branch of the aquaporin (major intrinsic protein) superfamily. Through heterologous expression in Xenopus laevis oocytes and the yeast (Saccharomyces cerevisiae) fps1(-) mutant, PtNIP1;1 has been shown to be an active aquaglyceroporin.
- Published
- 2001