High levels of intra- and inter-individual polymorphism in the rDNA ITS1 of Caulerpa racemosa (Chlorophyta)

Famà, Patrizia; Olsen, Jeanine L.; Stam, Wytze T.; Procaccini, Gabriele

doi:10.1017/s0967026200002948

Cited by 34 publications

(59 citation statements)

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“…lamourouxii (Turner) Weber-van Bosse f. requienii (Montagne) Weber-van Bosse), both confined at the central-eastern Mediterranean Sea and considered as typical seaweed components of the Lessepsian flora, with a non-aggressive character (Verlaque & al., 2000). All these varieties were accepted on the basis of morphological identification and molecular phylogenetic analyses (Famà & al., 2000;Durand & al., 2002;Verlaque & al., 2000Verlaque & al., , 2003.…”

Section: Introductionmentioning

confidence: 99%

“…This was due to similarities in gross morphology, conspicuous phenotypic plasticity or evidences from ecological performance and expansive behaviour of local populations. Nowadays, identification of these taxa can be achieved by means of fixed morphological features and genetic evidence (Famà & al., 2000;Durand & al., 2002;Verlaque & al., 2000Verlaque & al., , 2003Nuber & al., 2007;Sauvage & al., 2013;Belton & al., 2014).…”

Section: Introductionmentioning

confidence: 99%

“…The large number of the nuclear rDNA ITS1-5.8S-ITS2 region sequences obtained from specimens collected worldwide can be used to distinguish among Caulerpa taxa (Famà & al., 2000;Durand & al., 2002;Verlaque & al., 2000Verlaque & al., , 2003Nuber & al., 2007;Sauvage & al., 2013;Belton & al., 2014). Yet, to identify the "invasive taxon", a combination of morphological identikit and molecular data has been applied in solely 5 amongst the 13 Mediterranean countries in which C. racemosa sensu lato has been reported so far (France, Italy, Greece, Croatia and Cyprus) (reviewed in Klein & Verlaque, 2008), since the first report from Libya in 1990 (Nizamuddin, 1991) (see Fig.…”

Section: Introductionmentioning

confidence: 99%

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First record of <em>Caulerpa cylindracea</em> (Caulerpaceae, Chlorophyta) in Andalusia (Southern Spain)

Altamirano

Andreakis

Souza-Egipsy

et al. 2014

Anal. Jard. Bot. Madr.

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Three different species of Caulerpa (Caulerpaceae, Chlorophyta) cooccur in the Mediterranean Sea: two of them are found at the centraleastern basin and are typically considered non aggressive components of the Lessepsian flora [(C. chemnitzia (Esper) J.V. Lamouroux and C. racemosa var. lamourouxii (Turner) Weber-van Bosse f. requienii (Montagne) Weber van Bosse)]; a third taxon, C. cylindracea Sonder has aggressively expanded its range since its first observation in 1990, and it is nowadays reported from nearly all the Mediterranean countries. We report a population of C. cylindracea from Almería (Andalusia, Southern Iberian Peninsula) at −30 m depth as to be the westernmost record of the invasive variety on the Mediterranean European coast. Therefore, we made use of morphological description and molecular phylogenetics to provide a complete identification of this invasive seaweed in Southern Spain. Our findings are discussed in light of the composition of the receptor communities, such as maërl bed, edges of Posidonia oceanica (Linnaeus) Delile, and their ecology. Our results confirmed the suggested directionality of the invasive pathway to be westward to the Strait of Gibraltar, mainly supported by sea currents and vectors of anthropogenic origin.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

First record of <em>Caulerpa cylindracea</em> (Caulerpaceae, Chlorophyta) in Andalusia (Southern Spain)

Altamirano

Andreakis

Souza-Egipsy

et al. 2014

Anal. Jard. Bot. Madr.

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“…Of these, the first internal transcribed spacer (ITS1) diverges rapidly between closely related species, which has enabled it to be utilized for phylogenetic studies at or below the species level (e.g., Fabry et al 1999;Rodriguez-Perez et al 2006). Despite some success at investigating population relationships, intraindividual variation is common for this spacer, and unless a high level of sequence homogeneity has been maintained within species, it can obscure the resolution of phylogenetic trees (Miller et al 1996;Famà et al 2000). This variation is often due to internal repetition, in the form of microsatellites (Harris and Crandall 2000), or longer repeated sequences (Paskewitz et al 1993;van Herwerden et al 1999).…”

Section: Introductionmentioning

confidence: 99%

Internal Repetition and Intraindividual Variation in the rDNA ITS1 of the Anopheles punctulatus Group (Diptera: Culicidae): Multiple Units and Rates of Turnover

Bower

Cooper²,

Beebe

2009

J Mol Evol

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The rapid divergence of repetitive sequences makes them desirable markers for phylogenetic studies of closely related groups, provided that a high level of sequence homogeneity has been maintained within species. Intraspecific polymorphisms are found in an increasing number of studies now, and this highlights the need to determine why these occur. In this study we examined intraindividual variation present in the first ribosomal internal transcribed spacer (ITS1) from a group of cryptic mosquito species. Individuals of the Anopheles punctulatus group contained multiple ITS1 length variants that ranged from 1.2 to 8.0 kb. Nucleotide and copy number variation for several homologous internal repeats is common, yet the intraspecific sequence divergence of cloned PCR isolates is comparable to that of other mosquito species (*0.2-1.5%). Most of the length variation is comprised of a 5 0 -ITS1 repeat that was identified as a duplication of a conserved ITS2 region. Secondary structure conservation for this repeat is pronounced and several repeat types that are highly homogenized have formed. Significant interspecific divergence indicates a high rate of evolutionary change for this spacer. A maximum likelihood tree constructed here was congruent with previous phylogenetic hypotheses and suggests that concerted evolution is also accompanied by interpopulation divergence. The lack of interindividual differences and the presence of homogenized internal repeats suggest that a high rate of turnover has reduced the overall level of variation. However, the intraindividual variation also appears to be maintained by the absence of a single turnover rate and the complex dynamics of ongoing recombination within the spacer.

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“…However, previous examples that demonstrated spacer conservation (e.g., Fritz et al 1994;Schön et al 1998) have subsequently been refuted by intraindividual and intrapopulation sampling, coupled to the isolation of individual repeats by cloning (Onyabe and Conn 1999;Gandolfi et al 2001). Whether expected or not, the presence of intraindividual variation in the ITS1 can confound phylogenetic relationships (Famà et al 2000;Harris and Crandall 2000). There are also examples of length variation within individuals (Fenton et al 1998) and between closely related species (von der Schulenburg et al 2001).…”

Section: Introductionmentioning

confidence: 99%

Intraspecific Concerted Evolution of the rDNA ITS1 in Anopheles farauti Sensu Stricto (Diptera: Culicidae) Reveals Recent Patterns of Population Structure

Bower

Dowton

Cooper³

et al. 2008

J Mol Evol

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We examined the intraindividual variation present in the first ribosomal internal transcribed spacer (ITS1) of Anopheles farauti to determine the level of divergence among populations for this important malarial vector. We isolated 187 clones from 70 individuals and found regional variation among four internal tandem repeats. The data were partitioned prior to analysis given the presence of a paralogous ITS2 sequence, called the 5 0 -subrepeat, inserted in the ITS1 of most clones. A high level of homogenization and population differentiation was observed for this repeat, which indicates a higher rate of turnover relative to the adjacent 'core' region. Bayesian analysis was performed using several substitutional models on both a combined and a partitioned data set. On the whole, the ITS1 phylogeny and geographic origin of the samples appear to be congruent. Some interesting exceptions indicate the spread of variant repeats between populations and the retention of ancestral polymorphism. Our data clearly demonstrate concerted evolution at the intraspecific level despite intraindividual variation and a complex internal repeat structure from a species that occupies a continuous coastal distribution. A high rate of genomic turnover in combination with a high level of sequence divergence appears to be a major factor leading to its concerted evolution within these populations.

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High levels of intra- and inter-individual polymorphism in the rDNA ITS1 of Caulerpa racemosa (Chlorophyta)

Cited by 34 publications

References 0 publications

First record of <em>Caulerpa cylindracea</em> (Caulerpaceae, Chlorophyta) in Andalusia (Southern Spain)

First record of <em>Caulerpa cylindracea</em> (Caulerpaceae, Chlorophyta) in Andalusia (Southern Spain)

Internal Repetition and Intraindividual Variation in the rDNA ITS1 of the Anopheles punctulatus Group (Diptera: Culicidae): Multiple Units and Rates of Turnover

Intraspecific Concerted Evolution of the rDNA ITS1 in Anopheles farauti Sensu Stricto (Diptera: Culicidae) Reveals Recent Patterns of Population Structure

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