scholarly journals Karyotype asymmetry shapes diversity within the physaloids (Physalidinae, Physalideae, Solanaceae)

2020 ◽  
Author(s):  
Julieta Rodríguez ◽  
Rocío Deanna ◽  
Franco Chiarini
Keyword(s):  
Chromosome Number ◽  
Karyotype Evolution ◽  
Phylogenetic Signal ◽  
Monotypic Genus ◽  
Independent Events ◽  
Phylogenetic Methods ◽  
Karyotype Asymmetry ◽  
Chromosome Arm ◽  
Cytogenetic Analyses ◽  
Diploid Ancestor

AbstractWithin the cosmopolitan family Solanaceae, Physalideae is the tribe with the highest generic diversity (30 genera and more than 200 species). This tribe embraces subtribe Physalidinae, in which positions of some genera are not entirely resolved. Chromosomes may help on this goal, by providing information on the processes underlying speciation. Thus, cytogenetic analyses were carried out in the subtribe in order to establish its chromosome number and morphology. Physalidinae is characterized by x = 12 and most species shows a highly asymmetric karyotype. These karyotype traits were mapped onto a molecular phylogeny to test the congruence between karyotype evolution and clade differentiation. A diploid ancestor was reconstructed for the subtribe, and five to six polyploidy independent events were estimated, plus one aneuploidy event (X = 11 in the monotypic genus Quincula). Comparative phylogenetic methods showed that asymmetry indices and chromosome arm ratio (r) have a high phylogenetic signal, whereas the number of telocentric and submetacentric chromosomes presented a conspicuous amount of changes. Karyotype asymmetry allow us to differentiate genera within the subtribe. Overall, our study suggests that Physalidineae diversification has been accompanied by karyotype changes, which can be applied to delimit genera within the group.

scholarly journals Descending Dysploidy and Bidirectional Changes in Genome Size Accompanied Crepis (Asteraceae) Evolution

Genes ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1436
Author(s):  
Magdalena Senderowicz ◽  
Teresa Nowak ◽  
Magdalena Rojek-Jelonek ◽  
Maciej Bisaga ◽  
Laszlo Papp ◽  
...  
Keyword(s):  
Genome Size ◽  
Dna Sequences ◽  
Chromosome Numbers ◽  
Karyotype Evolution ◽  
Base Number ◽  
Ancestral State ◽  
Ancestral Genome ◽  
Independent Events ◽  
Karyotype Asymmetry ◽  
Major Direction

The evolution of the karyotype and genome size was examined in species of Crepis sensu lato. The phylogenetic relationships, inferred from the plastid and nrITS DNA sequences, were used as a framework to infer the patterns of karyotype evolution. Five different base chromosome numbers (x = 3, 4, 5, 6, and 11) were observed. A phylogenetic analysis of the evolution of the chromosome numbers allowed the inference of x = 6 as the ancestral state and the descending dysploidy as the major direction of the chromosome base number evolution. The derived base chromosome numbers (x = 5, 4, and 3) were found to have originated independently and recurrently in the different lineages of the genus. A few independent events of increases in karyotype asymmetry were inferred to have accompanied the karyotype evolution in Crepis. The genome sizes of 33 Crepis species differed seven-fold and the ancestral genome size was reconstructed to be 1 C = 3.44 pg. Both decreases and increases in the genome size were inferred to have occurred within and between the lineages. The data suggest that, in addition to dysploidy, the amplification/elimination of various repetitive DNAs was likely involved in the genome and taxa differentiation in the genus.

KARYOTYPE ASYMMETRY IN GALTONIA AND PSEUDOGALTONIA (HYACINTHACEAE)

2003 ◽  
Vol 60 (3) ◽  
pp. 569-579 ◽  
Author(s):  
L. L. FORREST ◽  
K. JONG
Keyword(s):  
Chromosome Number ◽  
Monotypic Genus ◽  
Karyotype Asymmetry

The karyotype of a recently described species of Galtonia (Hyacinthaceae), G. regalis, is described and its cytotaxonomic relationship to other members of the genus examined. Since conflicting cytological patterns for the genus exist in the literature, the chromosome compositions of the three other species, G. candicans, G. princeps and G. viridiflora, are re-investigated. This study demonstrates that the karyotype of Galtonia is uniformly asymmetrical and distinctively trimodal, with 2n=16. Also included in this investigation is the allied monotypic genus Pseudogaltonia. Its karyotype is also asymmetrical, but differs from Galtonia in its chromosome number of 2n=18, and in certain other features.

Cytotaxonomy of Allium (Amaryllidaceae) subgenera Cyathophora and Amerallium sect. Bromatorrhiza

Phytotaxa ◽  
2017 ◽  
Vol 331 (2) ◽  
pp. 185 ◽  
Author(s):  
MIN-JIE LI ◽  
XIAN-LIN GUO ◽  
JUAN LI ◽  
SONG-DONG ZHOU ◽  
QING LIU ◽  
...  
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Karyotype Evolution ◽  
Diploid Species ◽  
Basic Chromosome Number ◽  
Molecular Evidence ◽  
Basic Chromosome ◽  
Karyotype Asymmetry

In the present study, we examined the karyotype data of subg. Cyathophora and sect. Bromatorrhiza, to determine some disputed karyotypes (e.g., A. spicatum and A. fasciculatum), and further to estimate the karyotype evolution along their phylogenetic frameworks. Our results revealed a fairly stable basic chromosome number (x = 8) in subg. Cyathophora, and we therefore revised x = 8 as the basic chromosome number of A. spicatum, rather than x = 10 mostly due to misidentifications concerning A. fasciculatum. The karyotype asymmetry analyses for subg. Cyathophora indicated that, the karyotype evolution for diploid species showing a high karyotype similarity was mainly due to intrachromosomal changes, while the interchromosomal changes were linked to the evolution of tetraploid populations. However, indeed different dysploid basic chromosome numbers (x = 7, 10, 11) and greatly different karyotype patterns occurred in sect. Bromatorrhiza, corresponding to the subsections revealed by molecular evidence. The combined evidence suggested that species with x = 11 compose a segmental allotriploid complex. It was also indicated that karyotype pattern of polyploids usually is closely related with  their diploid progenitors.

Aspidistra revoluta, a new species from limestone areas in Chongqing, China

Phytotaxa ◽  
2016 ◽  
Vol 257 (3) ◽  
pp. 280 ◽  
Author(s):  
Hao Zhou ◽  
Si-rong Yi ◽  
Qi Gao ◽  
Jie Huang ◽  
Yu-jing Wei
Keyword(s):  
New Species ◽  
Chromosome Number ◽  
Average Length ◽  
Chromosome Complement ◽  
Pollen Grains ◽  
The Other ◽  
Morphological Comparison ◽  
Chongqing Municipality ◽  
Karyotype Asymmetry ◽  
A New Species

Aspidistra revoluta (Asparagaceae) is described and illustrated as a new species from limestone areas in southern Chongqing Municipality, China. The new species can be distinguished from the other Aspidistra species by its unique umbrella-like pistil with large revolute stigma lobes that bent downwards and touch the base of the perigone. A detailed morphological comparison among A. revoluta, A. nanchuanensis and A. carnosa is provided. The pollen grains of A. revoluta are subspherical and inaperturate, with verrucous exine. The chromosome number is 2n = 38, and the karyotype is formulated as 2n = 22m + 6sm + 10st. The average length of chromosome complement is 4.50 μm, and the karyotype asymmetry indexes A1 and A2 are respectively 0.37±0.03 and 0.49±0.01.

scholarly journals Phylogenomic analysis of echinoderm class relationships supports Asterozoa

2014 ◽  
Vol 281 (1786) ◽  
pp. 20140479 ◽  
Author(s):  
Maximilian J. Telford ◽  
Christopher J. Lowe ◽  
Christopher B. Cameron ◽  
Olga Ortega-Martinez ◽  
Jochanan Aronowicz ◽  
...  
Keyword(s):  
Convergent Evolution ◽  
Sea Urchins ◽  
Phylogenetic Signal ◽  
Strong Support ◽  
Phylogenomic Analysis ◽  
Phylogenetic Studies ◽  
Phylogenetic Methods ◽  
Complete Dataset ◽  
Type Larva ◽  
Molecular Phylogenetic

While some aspects of the phylogeny of the five living echinoderm classes are clear, the position of the ophiuroids (brittlestars) relative to asteroids (starfish), echinoids (sea urchins) and holothurians (sea cucumbers) is controversial. Ophiuroids have a pluteus-type larva in common with echinoids giving some support to an ophiuroid/echinoid/holothurian clade named Cryptosyringida. Most molecular phylogenetic studies, however, support an ophiuroid/asteroid clade (Asterozoa) implying either convergent evolution of the pluteus or reversals to an auricularia-type larva in asteroids and holothurians. A recent study of 10 genes from four of the five echinoderm classes used ‘phylogenetic signal dissection’ to separate alignment positions into subsets of (i) suboptimal, heterogeneously evolving sites (invariant plus rapidly changing) and (ii) the remaining optimal, homogeneously evolving sites. Along with most previous molecular phylogenetic studies, their set of heterogeneous sites, expected to be more prone to systematic error, support Asterozoa. The homogeneous sites, in contrast, support an ophiuroid/echinoid grouping, consistent with the cryptosyringid clade, leading them to posit homology of the ophiopluteus and echinopluteus. Our new dataset comprises 219 genes from all echinoderm classes; analyses using probabilistic Bayesian phylogenetic methods strongly support Asterozoa. The most reliable, slowly evolving quartile of genes also gives highest support for Asterozoa; this support diminishes in second and third quartiles and the fastest changing quartile places the ophiuroids close to the root. Using phylogenetic signal dissection, we find heterogenous sites support an unlikely grouping of Ophiuroidea + Holothuria while homogeneous sites again strongly support Asterozoa. Our large and taxonomically complete dataset finds no support for the cryptosyringid hypothesis; in showing strong support for the Asterozoa, our preferred topology leaves the question of homology of pluteus larvae open.

Changnienia malipoensis, a new species from China (Orchidaceae; Epidendroideae; Calypsoeae)

Phytotaxa ◽  
2013 ◽  
Vol 115 (2) ◽  
pp. 55 ◽  
Author(s):  
DONG-HUI PENG ◽  
ZHONG-JIAN LIU ◽  
JUN-WEN ZHAI
Keyword(s):  
New Species ◽  
Chromosome Number ◽  
Yunnan Province ◽  
Central China ◽  
Morphological Evidence ◽  
Monotypic Genus ◽  
Phylogenetic Placement ◽  
A New Species

Changnienia Chien (1935: 89) is a monotypic genus of tribe Calypsoeae endemic to eastern and central China (Chen et al. 1999, 2009, Freudenstein 2005), previously with only the species C. amoena Chien (1935: 90), which was listed in the Chinese Redbook in 1992 (Fu 1992). Yang & Zhu (1984) reported a chromosome number for it of 2n=46. Sun et al. (2006) observed pollination and found that Bombus trifasciatus was its pollinator. Zhai et al. (2013) confirmed the phylogenetic placement of this species as a member of tribe Calypsoeae (sensu Pridgeon et al. 2005). A new species of Changnienia is described and illustrated here based on molecular and morphological evidence. It is discovered in Malipo, Yunnan Province, China.

Karyological study in fifteen Leucocoryne taxa (Alliaceae)

Biologia ◽  
2012 ◽  
Vol 67 (2) ◽  
Author(s):  
Paola Jara-Arancio ◽  
Pedro Jara-Seguel ◽  
Claudio Palma-Rojas ◽  
Gina Arancio ◽  
Raul Moreno
Keyword(s):  
Chromosome Number ◽  
Secondary Constriction ◽  
Chromosome Morphology ◽  
Chromosome Size ◽  
Chromosome Fusion ◽  
Karyological Study ◽  
Karyotype Asymmetry ◽  
Additional Chromosome ◽  
Karyotype Formula ◽  
Haploid Karyotype

AbstractThe karyotype of fifteen Leucocoryne taxa was studied, assessing characteristics such as chromosome morphology and size, secondary constriction location, and asymmetry level. Two groups of Leucocoryne taxa were described based on chromosome number (2n = 10 and 2n = 18) and karyotype asymmetry. The haploid karyotype formula for the group 2n = 10 was 3m + 2st (or 2t), whereas for the group 2n = 18 was 7m + 2st (or 2t). Such results corroborate the karyotype descriptions previously carried out for some taxa of the genus. Leucocoryne taxa showed a high resemblance in chromosome morphology, but inter-specific differences were found in mean chromosome size. These data and previous studies based on gross chromosome morphology support Crosa’s hypothesis, which suggests that the cytotype 2n = 10 is diploid and perhaps ancestral, whereas that the cytotype 2n = 18 is tetraploid but with an additional chromosome fusion being probably a derived status.

scholarly journals Molecular Cytogenetic Characterization of the Sicilian Endemic Pond Turtle Emys trinacris and the Yellow-Bellied Slider Trachemys scripta scripta (Testudines, Emydidae)

Genes ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 702 ◽  
Author(s):  
Rita Scardino ◽  
Sofia Mazzoleni ◽  
Michail Rovatsos ◽  
Luca Vecchioni ◽  
Francesca Dumas
Keyword(s):  
Karyotype Evolution ◽  
Chromosomal Rearrangements ◽  
Trachemys Scripta ◽  
Turtle Species ◽  
Telomeric Sequences ◽  
Pond Turtle ◽  
Rdna Loci ◽  
Cytogenetic Analyses ◽  
Staining Methods ◽  
Emys Trinacris

Turtles, a speciose group consisting of more than 300 species, demonstrate karyotypes with diploid chromosome numbers ranging from 2n = 26 to 2n = 68. However, cytogenetic analyses have been conducted only to 1/3rd of the turtle species, often limited to conventional staining methods. In order to expand our knowledge of the karyotype evolution in turtles, we examined the topology of the (TTAGGG)n telomeric repeats and the rDNA loci by fluorescence in situ hybridization (FISH) on the karyotypes of two emydids: the Sicilian pond turtle, Emys trinacris, and the yellow-bellied slider, Trachemys scripta scripta (family Emydidae). Furthermore, AT-rich and GC-rich chromosome regions were detected by DAPI and CMA3 stains, respectively. The cytogenetic analysis revealed that telomeric sequences are restricted to the terminal ends of all chromosomes and the rDNA loci are localized in one pair of microchromosomes in both species. The karyotype of the Sicilian endemic E. trinacris with diploid number 2n = 50, consisting of 13 pairs of macrochromosomes and 12 pairs of microchromosomes, is presented here for first time. Our comparative examination revealed similar cytogenetic features in Emys trinacris and the closely related E. orbicularis, as well as to other previously studied emydid species, demonstrating a low rate of karyotype evolution, as chromosomal rearrangements are rather infrequent in this group of turtles.

Distribution of FISH oligo-5S rDNA and oligo-(AGGGTTT)3 in Hibiscus mutabilis L.

Genome ◽  
2021 ◽  
pp. 1-10
Author(s):  
Xiaomei Luo ◽  
Zhoujian He
Keyword(s):  
Chromosome Number ◽  
Physical Map ◽  
Molecular Cytogenetics ◽  
5S Rdna ◽  
Chromosome Length ◽  
Chromosome Identification ◽  
Karyotype Asymmetry ◽  
First Time ◽  
Distribution Of Fish

Hibiscus exhibits high variation in chromosome number both within and among species. The Hibiscus mutabilis L. karyotype was analyzed in detail using fluorescence in situ hybridization (FISH) with oligonucleotide probes for (AG3T3)3 and 5S rDNA, which were tested here for the first time. In total, 90 chromosomes were counted in prometaphase and metaphase, and all exhibited similarly intense (AG3T3)3 signals at both ends. (AG3T3)3 showed little variation and thus did not allow discrimination among H. mutabilis chromosomes, but its location at both ends confirmed the integrity of each chromosome, thus contributing to accurate counting of the numerous, small chromosomes. Oligo-5S rDNA marked the proximal/distal regions of six chromosomes: weak signals on chromosomes 7 and 8, slightly stronger signals on chromosomes 15 and 16, and very strong signals on chromosomes 17 and 18. Therefore, 5S rDNA could assist in chromosome identification in H. mutabilis. Metaphase chromosome lengths ranged from 3.00 to 1.18 μm, indicating small chromosomes. The ratios of longest to shortest chromosome length in prometaphase and metaphase were 2.58 and 2.54, respectively, indicating karyotype asymmetry in H. mutabilis. These results provide an exact chromosome number and a physical map, which will be useful for genome assembly and contribute to molecular cytogenetics in the genus Hibiscus.

Sign in / Sign up

Export Citation Format

Share Document