Analyses of ribosomal RNA sequences from glaucocystophyte cyanelles provide new insights into the evolutionary relationships of plastids

Helmchen, T; Bhattacharya, Debashish; Melkonian, Michael

doi:10.1007/bf00170674

Cited by 72 publications

(43 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The occurrence of murein in cyanelles resembles the situation in cyanobacteria, and is consistent with the retention of peptidoglycan in this early-branching (as shown by molecular genetic data) plastid (Helmchen et a/., 1995) in a host closely related to red and green algae (Bhattacharya et a/., 1995a). Regardless of the presence or absence of peptidoglycan walls, the division process in cyanobacteria, cyanelles and euplastids involves expression of the FtsZ gene (Beech & Gilson, 2000).…”

Section: Introductionsupporting

confidence: 72%

“…A. Raven. e-mail: j.a.raven@dundee.ac.uk (1995a) and Helmchen et al (1995) on nuclear and plastid rRNA sequences shows that the cyanelles of glaucocystophytes are evolutionarily close to green and non-green plastids. These data, and subsequent findings (Martin et al 1998;Tomitani et al, 1999;McFadden, 2001;Ting et al, 2002), are consistent with a monophyletic origin of plastids including cyanelles (cf.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Carboxysomes and peptidoglycan walls of cyanelles: possible physiological functions

Raven

2003

European Journal of Phycology

View full text Add to dashboard Cite

The cyanelles of glaucocystophyte (= glaucophyte) algae and the thecate amoeba Paulinella were previously thought to be endosymbiotic cyanobacteria or intermediates in the evolution of plastids from endosymbiotic cyanobacteria. While the more recent determinations of the number and nature of genes in the cyanelle genome show that cyanelles are genetically plastids, they have retained cyanobacterial features which are never (peptidoglycan walls) or only very rarely (carboxysomes) found in other plastids. The hypothesis presented here relates the peptidoglycan wall and the function of carboxysomes to the involvement of active water efflux using contractile vacuoles or their functional equivalent in volume regulation of noncyanelle compartments of the cell in at least some parts of the life cycle. The peptidoglycan wall could permit a relatively high intracyanelle osmolarity which is presumably needed for cyanelle growth. A high intracyaneUe osmolarity permits the high inorganic carbon concentration in the cyanelle during photosynthesis which is required for a carboxysome-based inorganic carbon concentration mechanism. The occurrence of a contractile-vacuole-based mechanism of volume regulation in at least part of the life cycle argues on energetic grounds for a low osmolarity of the cytosol, with a consequent lack of potential for a high inorganic carbon concentration in the cell as a whole. These predictions are suscepJible to experimental test.

show abstract

Section: Introductionsupporting

confidence: 72%

Section: Introductionmentioning

confidence: 99%

Carboxysomes and peptidoglycan walls of cyanelles: possible physiological functions

Raven

2003

European Journal of Phycology

View full text Add to dashboard Cite

show abstract

“…On the other hand C. caldarium contains 28 genes and not yet defined ORFs that have not been detected in any other plastid genome. Two additional genes (hisH and ycf49) are only present in a glaucocystophyte alga containing cyanelles, which are suggested to be "primitive" plastids, Cyanophora paradoxa (Helmchen et al 1995). In summary, 30 protein coding genes and ORFs are present in the cpgenome of C. caldarium that are not found in the cpgenome of P. purpurea.…”

Section: Structural Organization Of the Cp-genome Of C Caldariummentioning

confidence: 94%

The Structure and Gene Repertoire of an Ancient Red Algal Plastid Genome

Glöckner¹,

Rosenthal²,

Valentin

2000

J Mol Evol

133

View full text Add to dashboard Cite

Abstract. Photosynthetic eukaryotes can, according to features of their chloroplasts, be divided into two major groups: the red and the green lineage of plastid evolution. To extend the knowledge about the evolution of the red lineage we have sequenced and analyzed the chloroplast genome (cp-genome) of Cyanidium caldarium RK1, a unicellular red alga (AF022186). The analysis revealed that this genome shows several unusual structural features, such as a hypothetical hairpin structure in a genefree region and absence of large repeat units. We provide evidence that this structural organization of the cpgenome of C. caldarium may be that of the most ancient cp-genome so far described. We also compared the cpgenome of C. caldarium to the other known cp-genomes of the red lineage. The cp-genome of C. caldarium cannot be readily aligned with that of Porphyra purpurea, a multicellular red alga, or Guillardia theta due to a displacement of a region of the cp-genome. The phylogenetic tree reveals that the secondary endosymbiosis, through which G. theta evolved, took place after the separation of the ancestors of C. caldarium and P. purpurea.We found several genes unique to the cp-genome of C. caldarium. Five of them seem to be involved in the building of bacterial cell envelopes and may be responsible for the thermotolerance of the chloroplast of this alga. Two additional genes may play a role in stabilizing the photosynthetic machinery against salt stress and detoxification of the chloroplast. Thus, these genes may be unique to the cp-genome of C. caldarium and may be required for the endurance of the extreme living conditions of this alga.

show abstract

“…[44,[161][162][163]), 27 (15 significantly) -green plants (e.g. [46,51,164]) and 17 (6 significantly) -rhodophytes (e.g. [47,165,166]) -Tab.…”

Section: Testing the Relationships Among Archaeplastida Lineagesmentioning

confidence: 99%

Monophyly of Archaeplastida supergroup and relationships among its lineages in the light of phylogenetic and phylogenomic studies. Are we close to a consensus?

Mackiewicz

Gagat

2014

Acta Soc Bot Pol

View full text Add to dashboard Cite

One of the key evolutionary events on the scale of the biosphere was an endosymbiosis between a heterotrophic eukaryote and a cyanobacterium, resulting in a primary plastid. Such an organelle is characteristic of three eukaryotic lineages, glaucophytes, red algae and green plants. The three groups are usually united under the common name Archaeplastida or Plantae in modern taxonomic classifications, which indicates they are considered monophyletic. The methods generally used to verify this monophyly are phylogenetic analyses. In this article we review up-to-date results of such analyses and discussed their inconsistencies. Although phylogenies of plastid genes suggest a single primary endosymbiosis, which is assumed to mean a common origin of the Archaeplastida, different phylogenetic trees based on nuclear markers show monophyly, paraphyly, polyphyly or unresolved topologies of Archaeplastida hosts. The difficulties in reconstructing host cell relationships could result from stochastic and systematic biases in data sets, including different substitution rates and patterns, gene paralogy and horizontal/endosymbiotic gene transfer into eukaryotic lineages, which attract Archaeplastida in phylogenetic trees. Based on results to date, it is neither possible to confirm nor refute alternative evolutionary scenarios to a single primary endosymbiosis. Nevertheless, if trees supporting monophyly are considered, relationships inferred among Archaeplastida lineages can be discussed. Phylogenetic analyses based on nuclear genes clearly show the earlier divergence of glaucophytes from red algae and green plants. Plastid genes suggest a more complicated history, but at least some studies are congruent with this concept. Additional research involving more representatives of glaucophytes and many understudied lineages of Eukaryota can improve inferring phylogenetic relationships related to the Archaeplastida. In addition, alternative approaches not directly dependent on phylogenetic methods should be developed.

show abstract

Analyses of ribosomal RNA sequences from glaucocystophyte cyanelles provide new insights into the evolutionary relationships of plastids

Cited by 72 publications

References 42 publications

Carboxysomes and peptidoglycan walls of cyanelles: possible physiological functions

Carboxysomes and peptidoglycan walls of cyanelles: possible physiological functions

The Structure and Gene Repertoire of an Ancient Red Algal Plastid Genome

Monophyly of Archaeplastida supergroup and relationships among its lineages in the light of phylogenetic and phylogenomic studies. Are we close to a consensus?

Contact Info

Product

Resources

About