Organ regulated expression of Parasponia andersonii haemoglobin gene in transgenic tobacco plants.
Plant haemoglobin genes are known to occur in legume and non-legume families and in both nodulating (e.g., Parasponia andersonii) and non-nodulating species (e.g., Trema tomentosa). Their presence in non-nondulating plants raises the possibility that haemoglobins might serve a function in non-symbiotic tissues distinct from their role in the nitrogen-fixing root nodules induced by micro-organisms. We report here that a P. andersonii haemoglobin promoter can regulate expression of either the P. andersonii haemoglobin gene, or a hybrid construct with the bacterial chloramphenicol acetyltransferase gene (cat), in the non-symbiotic plant, Nicotiana tabacum. Expression is predominantly in the roots, implying that haemoglobins might have a function in roots of non-nodulated plants. We have also observed a low level of haemoglobin protein in non-nodulated P. andersonii roots, but not leaves, supporting this assertion. The expression in transgenic plants will allow further characterization of the promoter sequences essential for the organ-specific expression of haemoglobins in non-symbiotic tissues.
Landsmann
J
J
C.S.I.R.O. Division of Plant Industry, Canbera, A.C.T., Australia.
Llewellyn
D
D
Dennis
E S
ES
Peacock
W J
WJ
D000595:Amino Acid Sequence; D001483:Base Sequence; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D003001:Cloning, Molecular; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D006454:Hemoglobins / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010944:Plants / Q000235:genetics*; D010947:Plants, Toxic; D011401:Promoter Regions, Genetic; D014026:Nicotiana / Q000235:genetics*; D014170:Transformation, Genetic
D006454:Hemoglobins; D015500:Chloramphenicol O-Acetyltransferase