The light-independent pathway of chlorophyll synthesis which occurs in some lower plants and algae is still largely unknown. We have characterized a chloroplast mutant, H13, of Chlamydomonas reinhardtii which is unable to synthesize chlorophyll in the dark and is also photosystem I deficient. The mutant has a 2.8 kb deletion as well as other rearrangements of its chloroplast genome. By performing particle gun mediated chloroplast transformation of H13 with defined wild-type chloroplast DNA fragments, we have identified a new chloroplast gene, chlN, coding for a 545 amino acid protein which is involved in the light-independent accumulation of chlorophyll, probably at the step of reduction of protochlorophyllide to chlorophyllide. The chlN gene is also found in the chloroplast genomes of liverwort and pine, but is absent from the chloroplast genomes of tobacco and rice.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC556626 | PMC |
http://dx.doi.org/10.1002/j.1460-2075.1992.tb05220.x | DOI Listing |
Proc Natl Acad Sci U S A
February 2025
Molecular Genetics, Institute of Biology, Faculty of Life Sciences, Humboldt Universität zu Berlin, Berlin 10115, Germany.
The chloroplast genome encodes key components of the photosynthetic light reaction machinery as well as the large subunit of the enzyme central for carbon fixation, Ribulose-1,5-bisphosphat-carboxylase/-oxygenase (RuBisCo). Its expression is predominantly regulated posttranscriptionally, with nuclear-encoded RNA-binding proteins (RBPs) playing a key role. Mutants of chloroplast gene expression factors often exhibit impaired chloroplast biogenesis, especially in cold conditions.
View Article and Find Full Text PDFFront Plant Sci
January 2025
College of Forestry, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China.
Introduction: Plant physiology response and adaptation to drought stress has become a hotspot in plant ecology and evolution. possesses high ecological, ornamental and economic benefits. It has large root system and tolerance to cold, drought and poor soil.
View Article and Find Full Text PDFEnviron Microbiome
January 2025
School of Natural Sciences, Bangor University, Bangor, UK.
Background: Acquiring representative bacterial 16S rRNA gene community profiles in plant microbiome studies can be challenging due to the excessive co-amplification of host chloroplast and mitochondrial rRNA gene sequences that reduce counts of plant-associated bacterial sequences. Peptide Nucleic Acid (PNA) clamps prevent this by blocking PCR primer binding or binding within the amplified region of non-target DNA to stop the function of DNA polymerase. Here, we applied a universal chloroplast (p)PNA clamp and a newly designed mitochondria (m)PNA clamp to minimise host chloroplast and mitochondria amplification in 16S rRNA gene amplicon profiles of leaf, bark and root tissue of two oak species (Quercus robur and Q.
View Article and Find Full Text PDFPlant Physiol Biochem
January 2025
Plant Sciences and Agrotechnology Division, Indian Institute of Integrative Medicine (CSIR), Canal Road, Jammu, J & K, 180001, India; Academy of Scientific and Innovative Research, Ghaziabad, Uttar Pradesh, 201002, India. Electronic address:
Transplantation experiments conducted in high altitude ecosystems are rising as key strategy to examine the response of individual plant transplanted across distinct elevations. However, plant physiological and biochemical performance in response to changes in abiotic factors across different species and mountain ranges is still lacking. So in the present study, we have made an attempt to link the physiological performance with that of altitudinal gradient in Ladakh by transplanting Lepidium latifolium at four different altitudinal sites.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!