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101.
102.
Tomato (Lycopersicon esculentum Mill. cv. Moneymaker) plants have been wounded to induce the accumulation of proteinase-inhibitor proteins (PI proteins) at the local site of injury and systemically in unwounded tissues. To determine the range of genes affected in the wound-response, polysomal mRNA has been isolated from the damaged leaves and from systemically responding leaves over a time-course of 2, 4, 10 and 24 h after wounding. Changes in the pattern of 35S-translation products indicate that the events that occur at the local wound-site are different from those that occur systemically, both with respect to the number of genes that are regulated and the timing of their regulation. In order to compare the effects of wounding and an endogenous systemic signal generated at the wound-site with those of elicitor (proteinase-inhibitor-inducing factor, PIIF) treatment of excised plants, polysomal mRNA has also been isolated from leaves of plants over a time-course of 2, 4, 10 and 24 h after PIIF-treatment. Changes in the pattern of 35S-translation products indicates that the events induced by PIIF resemble those induced by mechanical injury, rather than those induced by the endogenous systemic signal.Abbreviations IFF
isoelectric focussing
- PI proteins
proteinase inhibitor proteins
- PIIF
proteinase-inhibitor-inducing factor
- ssRubisco
small subunit of ribulose-1,5-bisphosphate carboxylase 相似文献
103.
C. HOWARTH 《Plant, cell & environment》1989,12(5):471-477
Abstract The capacity to synthesize heat shock proteins (HSPs) during seed germination of sorghum (Sorghum bicolor) and pearl millet (Pennisetum americanum) has been examined. HSP synthesis is detectable in a thermotolerant genotype of sorghum during the first hour of imbibition of the seed under high temperature stress. A non-coordinate control of HSP synthesis during germination was revealed. Genotypic differences were manifest in the stage of germination at which the ability to synthesize HSPs was first apparent and this related to the thermosensitivity of that genotype. 相似文献
104.
105.
The chalcone synthase multigene family of Petunia hybrida (V30): differential,light-regulated expression during flower development and UV light induction 总被引:11,自引:0,他引:11
We have analysed the expression of the 8–10 members of the gene family encoding the flavonoid biosynthetic enzyme chalcone synthase (CHS) from Petunia hybrida. During normal plant development only two members of the gene family (CHS-A and CHS-J) are expressed. Their expression is restricted to floral tissues mainly. About 90% of the total CHS mRNA pool is transcribed from CHS-A, wheares CHS-J delivers about 10% in flower corolla, tube and anthers. Expression of CHS-A and CHS-J during flower development is coordinated and (red) light-dependent. In young seedlings and cell suspension cultures expression of CHS-A and CHS-J can be induced with UV light. In addition to CHS-A and CHS-J, expression of another two CHS genes (CHS-B and CHS-G) is induced in young seedlings by UV light, albeit at a low level. In contrast to CHS genes from Leguminoseae, Petunia CHS genes are not inducible by phytopathogen-derived elicitors. Expression of CHS-A and CHS-J is reduced to a similar extent in a regulatory CHS mutant, Petunia hybrida Red Star, suggesting that both genes are regulated by the same trans-acting factors. Comparison of the promoter sequences of CHS-A and CHS-J reveals some striking homologies, which might represent cis-acting regulatory sequences. 相似文献
106.
Kees W. Rodenburg Marcel J. A. de Groot Rob A. Schilperoort Paul J. J. Hooykaas 《Plant molecular biology》1989,13(6):711-719
In relation to the question which DNA form (single- or double-stranded) is transferred by Agrobacterium tumefaciens to plant cells, we studied the behaviour of single-stranded DNA, as compared to double-stranded DNA, when it is introduced into plant protoplasts by electroporation. To this end, we cloned a construct with a plant NPTII gene as well as a CAT gene in the M13 vectors tg130 and tg131. We found that both complementary single-stranded molecules gave rise to substantial CAT activity in plant protoplasts, suggesting that single-stranded DNA is converted into double-stranded DNA by the plant cell replication machinery. Unexpectedly, we found that single-stranded DNA leads to a 3–10 fold higher frequency of stable transformation (selection for kanamycin resistance) than double-stranded DNA. These results indicate that the use of single-stranded DNA might be considered in experiments in which optimal transformation frequencies are needed, e.g. with protoplasts form recalcitrant plant species.Abbreviations ss
single-stranded
- ds
double-stranded
- CAT
chloramphenicol acetyl transferase
- NPTII
neomycin phosphotransferase II
- RT
room temperature 相似文献
107.
108.
109.
Francisco Javier Caballero Isabel Igeño Jacobo Cárdenas Francisco Castillo 《Archives of microbiology》1989,152(5):508-511
The phototrophic bacterium Rhodobacter capsulatus E1F1 assimilates ammonia and other forms of reduced nitrogen either through the GS/GOGAT pathway or by the concerted action of l-alanine dehydrogenase and aminotransferases. These routes are light-independent and very responsive to the carbon and nitrogen sources used for cell growth. GS was most active in cells grown on nitrate or l-glutamate as nitrogen sources, whereas it was heavily adenylylated and siginificantly repressed by ammonium, glycine, l-alanine, l-aspartate, l-asparagine and l-glutamine, under which conditions specific aminotransferases were induced. GOGAT activity was kept at constitutive levels in cells grown on l-amino acids as nitrogen sources except on l-glutamine where it was significantly induced during the early phase of growth. In vitro, GOGAT activity was strongly inhibited by l-tyrosine and NADPH. In cells using l-asparagine or l-aspartate as nitrogen source, a concerted induction of l-aspartate aminotransferase and l-asparaginase was observed. Enzyme level enhancements in response to nitrogen source variation involved de novo protein synthesis and strongly correlated with the cell growth phase.Abbreviations ADH
l-alanine dehydrogenase
- AOAT
l-alanine:2-oxoglutarate aminotransferase
- Asnase
l-asparaginase
- GOAT
Glycine: oxaloacetate aminotransferase
- GOGAT
Glutamate synthase
- GOT
l-aspartate: 2-oxoglutarate aminotransferase
- GS
Glutamine synthetase
- HPLC
High-Pressure Liquid Chromatography
- MOPS
2-(N-morpholino)propanesulfonic acid
- MSX
l-methionine-d,l-sulfoximine 相似文献
110.