@article {345,
	title = {Pseudo-nitzschia pungens and Pseudo-nitzschia multiseries (Bacillariophyceae) - Nuclear ribosomal DNAs and species differences},
	journal = {Journal of Phycology},
	volume = {31},
	number = {3},
	year = {1995},
	note = {Times Cited: 25ArticleEnglishCited References Count: 53Rf344},
	month = {JUN},
	pages = {421-427},
	abstract = {The region of the nuclear ribosomal DNA (rDNA) operon containing the small subunit (SSU), internal transcribed spacer 1 (ITS1), and a portion of the 5.8S rDNA gene was sequenced in one isolate each of Pseudo-nitzschia multiseries (Hasle) Hasle and Pseudo-nitzschia pungens (Grunow in Cleve \& Moller) Hasle. The SSUs of these two species were highly similar, differing only in 24 point mutations and one insertion/ deletion in 2774 bp. The ITS1 sequences were more variable, with 57 point mutations and three insertion/deletions in 257 bp. There were no differences in 44 bp of the 5.8S sequences. Restriction fragment patterns (RFPs) for the restriction endonucleases HaeIII, HhaI, and RsaI for 13 isolates of P. multiseries from the Atlantic, Pacific, and Gulf coasts of the United States and 16 isolates of P. pungens from the three coasts of the United States, in addition to Japan and China, were compared. There were differences between the RFPs of P. multiseries and P. pungens that corresponded to sites mapped by the DNA sequences, but no intraspecific variation in RFPs was observed for either species. The differences in RFPs correlate with morphological, immunological, and other rDNA differences and support the recognition of these taxa as separate species.},
	keywords = {algae, Bacillariophyta, canada, diatom, domoic-acid, internal transcribed spacer (ITS), p-pungens, phylogeny, phytoplankton, polymorphisms, Pseudo-nitzschia multiseries, restriction fragment pattern (RFP), ribosomal DNA (rDNA), sequences, shellfish, small subunit (SSU), waters},
	url = {<Go to ISI>://A1995RF34400014},
	author = {Manhart, J. R. and G. A. Fryxell and M. C. Villac and Segura, L. Y.}
}
@proceedings {215,
	title = {Domoic acid toxicity of large new cells of Pseudo-nitzschia multiseries resulting from sexual reproduction},
	volume = {2261},
	year = {1999},
	month = {Feb 1999},
	pages = {21-26},
	address = {Ottowa ON},
	abstract = {During normal vegetative growth in culture, the pennate diatom Pseudo-nitzschia multiseries decreases in cell length and also in cellular content of the neurotoxin domoic acid (DA), causative agent of Amnesic Shellfish Poisoning. Diatoms commonly undergo sexual reproduction in order to regenerate their large cell size. Sexual reproduction in species Pseudo-nitzschia was recently documented. After mixing exponentially growing cells of the opposite mating type and of the appropriate minimal size, pairing was observed of parent cells, gamete production, fusion of gametes to form zygotes, and enlargement of auxospores within which formed the long initial cells. The latter are called {\textquoteleft}large new cells{\textquoteright} after they exit auxospores and undergo the first vegetative division. This paper documents the DA production by large new cells, relative to parent cells. Also reported is the range of cell sizes that favour auxosporulation. Such information may provide insights into the timing and toxicity of Pseudo-nitzschia spp. blooms in the field.},
	keywords = {Algal, Algal blooms, Bacillariophyta, Biological poisons, Cell culture, Cells, culture, dangerous organisms, Environmental Regime:, life cycle, Marine, medicines, Pseudo-nitzschia multiseries, Public health, Q1 01461 Plankton, Q1 01484 Species interactions: parasites and diseases, Q3 01585 Plant, Q5 01524, Reproduction, Toxicity, Toxicology},
	author = {Bates, S. S. and Hiltz, M. F. and Leger, C.}
}
@article {238,
	title = {Sexual reproduction, mating system, chloroplast dynamics and abrupt cell size reduction in seudo-nitzschia pungens from the North Sea (Bacillariophyta)},
	journal = {European Journal of Phycology},
	volume = {40},
	number = {4},
	year = {2005},
	note = {Times Cited: 0ArticleEnglishCited References Count: 64996cf},
	month = {NOV},
	pages = {379-395},
	abstract = {Clonal cultures of Pseudo-nitzschia pungens were isolated at various times from seven sites in the North Sea. During the mitotic cell cycle, the two plate-shaped chloroplasts were girdle-appressed during interphase and mitosis. After cytokinesis, the chloroplasts moved onto the parental valve and remained there during the formation of the new hypovalve and until separation and re-arrangement of the sibling cells within the cell chain had been completed. Clones were almost always heterothallic and cultures of opposite mating type isolated from different localities were compatible. Meiosis I was cytokinetic and accompanied by chloroplast division. Meiosis II involved karyokinesis but not cytokinesis and preceded the rearrangement and contraction of the two gametes. Sexual reproduction involved physiological anisogamy. With one exception, gamete behaviour was clone-specific, gametes being active in clones of one mating type but passive in clones of the other mating type. Auxospore development was accompanied by deposition of a transverse and then a longitudinal perizonium. Infrequently, triploid auxospores and presumably haploid auxospores were produced. The four chloroplasts of diploid auxospores did not divide, and behaved synchronously during the two acytokinetic mitotic cycles accompanying the deposition of the initial thecae. Just before the first division of the initial cell, the chloroplasts shifted onto the valves ( two per valve). The division of the initial cell was not accompanied by chloroplast division and so the two daughter cells received two chloroplasts each. Two modes of abrupt cell size reduction were detected. One occurred during initial cell formation when part of the expanded auxospore aborted. The other pattern was more gradual and was observed in growing cultures; during successive cell divisions a frustule constriction appeared and intensified, one chloroplast split into two, and part of the protoplast aborted. A simple naming system is proposed for mating types in pennate diatoms.},
	keywords = {abrupt size reduction, auxospore formation, auxosporulation, Bacillariophyta, chloroplast, complex bacillariophyceae, delicatissima bacillariophyceae, diatoms, domoic acid production, genus, heterothally, marine diatom, mating system, multiseries bacillariophyceae, pennate diatoms, Pseudo-nitzschia, rapid evolution, sellaphora, sexual reproduction},
	url = {<Go to ISI>://000234151300006},
	author = {Chepurnov, V. A. and Mann, D. G. and Sabbe, K. and Vannerum, K. and Casteleyn, G. and Verleyen, E. and Peperzak, L. and Vyverman, W.}
}
