Search results for "Gametophyte"
showing 7 items of 7 documents
Identification of the phosphoglycerate dehydrogenase isoform EDA9 as the essential gene for embryo and male gametophyte development in Arabidopsis
2013
[EN] Three different pathways of serine (Ser) biosynthesis have been described in plants: the Glycolate pathway, which is part of the Photorespiratory pathway, and 2 non-Photorespiratory pathways, the Glycerate and the Phosphorylated pathways. The Phosphorylated Pathway of Ser Biosynthesis (PPSB) has been known to exist since the 1950s, but its biological relevance was not revealed until quite recently when the last enzyme of the pathway, the Phosphoserine Phosphatase, was functionally characterized. In the associated study1, we characterized a family of genes coding for putatite phosphoglycerate dehydrogenases (PGDH, 3-PGDH, and EDA9), the first enzyme of the PPSB. A metabolomics study usi…
Unique Epigenetic Features of Ribosomal RNA Genes (rDNA) in Early Diverging Plants (Bryophytes)
2019
Introduction: In plants, the multicopy genes encoding ribosomal RNA (rDNA) typically exhibit heterochromatic features and high level of DNA methylation. Here, we explored rDNA methylation in early diverging land plants from Bryophyta (15 species, 14 families) and Marchantiophyta (4 species, 4 families). DNA methylation was investigated by methylation-sensitive Southern blot hybridization in all species. We also carried out whole genomic bisulfite sequencing in Polytrichum formosum (Polytrichaceae) and Dicranum scoparium (Dicranaceae) and used available model plant methyloms (Physcomitrella patents and Marchantia polymorpha) to determine rDNA unit-wide methylation patterns. Chromatin structu…
Porphyra (Bangiophyceae) Transcriptomes Provide Insights Into Red Algal Development And Metabolism.
2012
The red seaweed Porphyra (Bangiophyceae) and related Bangiales have global economic importance. Here, we report the analysis of a comprehensive transcriptome comprising ca. 4.7 million expressed sequence tag (EST) reads from P. umbilicalis (L.) J. Agardh and P. purpurea (Roth) C. Agardh (ca. 980 Mbp of data generated using 454 FLX pyrosequencing). These ESTs were isolated from the haploid gametophyte (blades from both species) and diploid conchocelis stage (from P. purpurea). In a bioinformatic analysis, only 20% of the contigs were found to encode proteins of known biological function. Comparative analysis of predicted protein functions in mesophilic (including Porphyra) and extremophilic …
Orthotrichum karoo (Orthotrichaceae), a new species with hyaline-awned leaves from southwestern Africa
2009
A new Orthotrichum species, 0. karoo, is described. The moss has a gametophyte similar to that of 0. diaphanum, from which it mainly differs in its peristome lacking exostome teeth. It is known from three localities in western South Africa, and from one more in southern Namibia. In all these localities it was found growing on shrubs and trees, rarely on rocks, in succulent karoo and related types of vegetation.
Serine in plants: biosynthesis, metabolism, and functions
2014
Serine (Ser) has a fundamental role in metabolism and signaling in living organisms. In plants, the existence of different pathways of Ser biosynthesis has complicated our understanding of this amino acid homeostasis. The photorespiratory glycolate pathway has been considered to be of major importance, whereas the nonphotorespiratory phosphorylated pathway has been relatively neglected. Recent advances indicate that the phosphorylated pathway has an important function in plant metabolism and development. Plants deficient in this pathway display developmental defects in embryos, male gametophytes, and roots. We propose that the phosphorylated pathway is more important than was initially thou…
The essential role of the phosphorylated pathway of serine biosynthesis inArabidopsis
2013
[EN] In plants, 3 different pathways of serine biosynthesis have been described: the Glycolate pathway, which is associated with photorespiration, and 2 non-photorespiratory pathways, the Glycerate and the Phosphorylated pathways. The Phosphorylated Pathway of Serine Biosynthesis (PPSB) has been known since the 1950s, but has been studied relatively little, probably because it was considered of minor significance as compared with the Glycolate pathway. In the associated study1 , we described for the first time in plants the in vivo functional characterization of the PPSB, by targeting the phosphoserine phosphatase (PSP1), the last enzyme of the pathway. Following a gain—and loss-of-function…
Über den Allantoinstoffwechsel des Laubmooskallus und seine Beeinflussung durch Licht
1972
Summary 1. The amount of allantoin and allantoate was determined in moss callus grown under various light conditions. It can reach 26,5 % of the plant nitrogen content. The accumulation is influenced by light intensity and colour. 2. Red-light (660 nm) causes a greater allantoin level in the cells than blue light and white light illumination. Red-light favours the formation of young setae from the moss callus. We could detect a relation between the intensity of seta-development and the amount of allantoin. The accumulation is increasing with the growth of the setae. 3. Blue-light (440 nm) enhances the chlorophyll synthesis and promotes chloroplast develop ment. This effect is correlated wit…