Biomaterial Database

Phosphorylation of tobacco eukaryotic translation initiation factor 4A upon pollen tube germination. 1998

R G op den Camp, and C Kuhlemeier

Institute of Plant Physiology, University of Berne, Altenbergrain 21, CH-3013 Berne, Switzerland.

Eukaryotic translation initiation factor eIF-4A is a member of the DEAD box family of RNA helicases and RNA-dependent ATPases. In tobacco, eIF-4A is encoded by a gene family with one isoform, eIF-4A8, being exclusively expressed in pollen. This pollen-specific isoform is a candidate for mediating translational control in the developing gametophyte. Here we show that eIF-4A is barely phosphorylated in mature pollen, but during pollen tube germination, two isoforms of eIF-4A become phosphorylated. Phosphoamino acid analysis indicated phosphorylation of threonine. In order to determine whether pollen-specific eIF-4A8 is among the phosphorylated isoforms, we raised transgenic tobacco plants overexpressing eIF-4A8 containing a histidine tag. Hereby, we could show that indeed eIF-4A8 is modified through phosphorylation. The biological relevance of the phosphorylation of eIF-4A is discussed.

UI	MeSH Term	Description	Entries
D010448	Peptide Initiation Factors	Protein factors uniquely required during the initiation phase of protein synthesis in GENETIC TRANSLATION.	Initiation Factors,Initiation Factor,Factors, Peptide Initiation,Initiation Factors, Peptide
D010766	Phosphorylation	The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.	Phosphorylations
D010947	Plants, Toxic	Plants or plant parts which are harmful to man or other animals.	Plants, Poisonous,Plant, Poisonous,Plant, Toxic,Poisonous Plant,Poisonous Plants,Toxic Plant,Toxic Plants
D011058	Pollen	The fertilizing element of plants that contains the male GAMETOPHYTES.	Male Gametes, Plant,Male Gametophytes,Microspores, Plant,Plant Microspores,Pollen Grains,Gamete, Plant Male,Gametes, Plant Male,Gametophyte, Male,Gametophytes, Male,Grain, Pollen,Grains, Pollen,Male Gamete, Plant,Male Gametophyte,Microspore, Plant,Plant Male Gamete,Plant Male Gametes,Plant Microspore,Pollen Grain
D011233	Precipitin Tests	Serologic tests in which a positive reaction manifested by visible CHEMICAL PRECIPITATION occurs when a soluble ANTIGEN reacts with its precipitins, i.e., ANTIBODIES that can form a precipitate.	Precipitin Test,Test, Precipitin,Tests, Precipitin
D011994	Recombinant Proteins	Proteins prepared by recombinant DNA technology.	Biosynthetic Protein,Biosynthetic Proteins,DNA Recombinant Proteins,Recombinant Protein,Proteins, Biosynthetic,Proteins, Recombinant DNA,DNA Proteins, Recombinant,Protein, Biosynthetic,Protein, Recombinant,Proteins, DNA Recombinant,Proteins, Recombinant,Recombinant DNA Proteins,Recombinant Proteins, DNA
D014026	Nicotiana	A plant genus of the family SOLANACEAE. Members contain NICOTINE and other biologically active chemicals; the dried leaves of Nicotiana tabacum are used for SMOKING.	Tobacco Plant,Nicotiana tabacum,Plant, Tobacco,Plants, Tobacco,Tobacco Plants
D015153	Blotting, Western	Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.	Immunoblotting, Western,Western Blotting,Western Immunoblotting,Blot, Western,Immunoblot, Western,Western Blot,Western Immunoblot,Blots, Western,Blottings, Western,Immunoblots, Western,Immunoblottings, Western,Western Blots,Western Blottings,Western Immunoblots,Western Immunoblottings
D015180	Electrophoresis, Gel, Two-Dimensional	Electrophoresis in which a second perpendicular electrophoretic transport is performed on the separate components resulting from the first electrophoresis. This technique is usually performed on polyacrylamide gels.	Gel Electrophoresis, Two-Dimensional,Polyacrylamide Gel Electrophoresis, Two-Dimensional,2-D Gel Electrophoresis,2-D Polyacrylamide Gel Electrophoresis,2D Gel Electrophoresis,2D PAGE,2D Polyacrylamide Gel Electrophoresis,Electrophoresis, Gel, 2-D,Electrophoresis, Gel, 2D,Electrophoresis, Gel, Two Dimensional,Polyacrylamide Gel Electrophoresis, 2-D,Polyacrylamide Gel Electrophoresis, 2D,Two Dimensional Gel Electrophoresis,2 D Gel Electrophoresis,2 D Polyacrylamide Gel Electrophoresis,Electrophoresis, 2-D Gel,Electrophoresis, 2D Gel,Electrophoresis, Two-Dimensional Gel,Gel Electrophoresis, 2-D,Gel Electrophoresis, 2D,Gel Electrophoresis, Two Dimensional,PAGE, 2D,Polyacrylamide Gel Electrophoresis, 2 D,Polyacrylamide Gel Electrophoresis, Two Dimensional,Two-Dimensional Gel Electrophoresis
D019606	Phosphoamino Acids	Amino acids that contain phosphorus as an integral part of the molecule.	Amino Acids, Phosphorus,Acids, Phosphoamino,Acids, Phosphorus Amino,Phosphorus Amino Acids