Abstract
Green pea plants respond to light stress by expression of a nuclear ELIP (early light-inducible protein) gene. Here we report that the accumulation of ELIP transcript in pea plants during light stress is enhanced by low temperature treatment. The enhanced level of ELIP transcript during combined light and cold stress was found to be due to an increased stability of ELIP messenger RNA under these conditions. This transcript is translatable in vitro. In vivo, however, the amount of accumulated protein in the thylakoids declines with the decrease in the temperature because the translational activity is strongly reduced already at 10 degrees C. Plants exposed to light stress at temperatures that do not allow accumulation of ELIP transcript respond by induction of ELIP mRNA and protein during recovery at low light intensity and ambient temperature. The amount of protein that accumulates as a result of this "memory effect" is, however, much lower than that which accumulates as a result of direct light stress. The memory of a perceived light stress persists in plants stored at low temperature for at least 3 h, and the stress response can be released after an increase in temperature. Prolonged cold treatment, however, has a negative effect on the translatability of the ELIP transcript that accumulates during recovery.
Highlights
Wereport that the accumulatoiofnELIPtranscript photosystem I1 (PS 111, degradation of D l protein, and changes in pea plants during ligshttress is enhanced by low tem- in thelevel of pigments (Adamska et al, 1993)
The conditions have been reported to exist in the unicellular alga Dunaliella bardawil (Lers et al, 1991; Levy et al, 1992).A desiccation- and light-induced proteinrelated to Early light-inducible proteins (ELIPs) hbaseen described for the resurrection plant Craterostigmaplantagineum (Bartels et al, 1992)
In thiswork we report be stable under light stressconditions but is degraded during that the abundanceof ELIP transcript is positively regulated recovery from light stressat low light intensity(Adamska et al, by cold stress
Summary
$To whom correspondence should be addressed.Tel.: 49-511-762- Growth of Plants and Illumination-Pea plants Theabbreviations used are: ELIP(s), early light-induciblepro- under a light regime of 12 h darWl2 h light (lightfrom 08:OO to 20:OO). Tein(s1; LHCP, light-harvestingchlorophyll alb protein; E, einstein; p s The high light treatment was performed on detached mature leaves. Expression of ELIP Gene unCdoenrditions of Stress tures of thewaterbathswere 5, 10,15,and 2 0 T , respectively. A temperature of 0 "C was achieved by addition of ice to the water bath. Fraredradiation by a water bath containing a 3-cm waterlayer.In various experiments light intensitiesof 2,000-3,000 pE/m's were used because it hasbeen shown before that ELIP transcription saturates at levels as low as 1,000-1,500 pE/m's (Adamska et dl., 1992a). Isolation and Assay of RNA-Poly(A+) RNA was isolatedas described (Potter andKloppstech, 1993) usingoligo(dT)-cellulosechromatography (Pemherton et al, 1975).I n vitro translation was performed using the wheat germ system according to Roberts and Paterson (1973) in the presence of 1:"Slmethionine (Amersham Corp.).Dot blot hybridization was performed using a '"P-labeled random-primed homologous cDNA insert of ELIP clone p17C2 (Kolanus et al, 1987) or LHCIIclone (Otto et al, 1988)according to Amersham protocol
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
