Nucleotide sequence of the internal transcribed spacers and 5.8s region of ribosomal DNA inPhus pineaL

Abstract

The nucleotide sequence of the first internal transcribed spacer (ITS1) belonging to different ribosomal RNA genes from Pinus pinea are reported. The analyzed ITS1 can be distinguished on the basis of their length, being one 2631 bp and the other 271 bp long. Nucleotide comparison of these regions did not show appreciable sequence homology. The larger ITS1 contains five tandem arranged subrepeats with size ranging between 219 bp and 237 bp. The nucleotide sequence of the 5.8S and the ITS2 regions belonging to the larger ribosomal RNA gene are also reported.

Variation in the nrDNA ITS of Pinus Subsection Cembroides: Implications for Molecular Systematic Studies of Pine Species Complexes

“…The ITS region of subgenus Strobus shares many similarities with other available complete ITS sequences from Pinaceae, which are limited to P. pinea (Marrocco et al, 1996), Larix, and Pseudotsuga (Gernandt and Liston, 1999). Table 2 also includes length and GC content statistics for complete ITS1 and ITS2 sequences for Picea abies (Maggini et al, 2000) and complete 5.8S and ITS2 sequences for three North American species of Picea, P. glauca, P. mariana, and P. rubens (Germano and Klein, 1999).…”

“…The sister relationship between subgenus Strobus and subgenus Pinus is fairly well established Wang et al, 1999). Therefore, we have included the previously published (Marrocco et al, 1996) complete sequence of an ITS clone from Pinus pinea (subgenus Pinus) as an outgroup.…”

“…Because PIN2451 matches the most conserved part of the ITS1 subrepeats, it annealed to multiple sites in ITS1. Since it could not be used for sequencing PCR products that included more P. pinea L. X87935 Marrocco et al (1996) than one subrepeat, a PCR amplification was performed with PIN2451 and 26S25R. The smallest of several amplification products (approximately 700 bp) was gel purified, and a sequencing read was obtained with PIN2451.…”

“…Up to one half of the ITS1 length in Pinaceae is made up of subrepeats, most of which occur near the 3Ј end of the spacer (Marrocco et al, 1996;Vining and Campbell, 1997;Gernandt and Liston, 1999;Maggini et al, 2000). Although some conserved portions of ITS1 and ITS2 have been shown to be involved in pre-rRNA processing, most appear to be free of selective constraints.…”

Phylogenetics ofPinus(Pinaceae) Based on Nuclear Ribosomal DNA Internal Transcribed Spacer Region Sequences

“…3000-bp ITS region containing five ca. 250-bp subrepeats in the ITS-1 Marrocco et al, 1996). In order to estimate phylogenetic relationships among pine species using a nuclear locus, approximately 650 bp of nucleotide sequence from the 3Ј ITS region were obtained from 47 Pinus species and 2 species of Cathaya and Picea used as outgroups.…”