scholarly journals A Lineage of Begomoviruses Encode Rep and AC4 Proteins of Enigmatic Ancestry: Hints on the Evolution of Geminiviruses in the New World

Viruses ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 644 ◽  
Author(s):  
Sandra Iliana Torres-Herrera ◽  
Angélica Romero-Osorio ◽  
Oscar Moreno-Valenzuela ◽  
Guillermo Pastor-Palacios ◽  
Yair Cardenas-Conejo ◽  
...  
Keyword(s):  
Recombination Event ◽  
Replication Origin ◽  
New World ◽  
Plant Pathogens ◽  
Squash Leaf Curl Virus ◽  
Rep Proteins ◽  
Cenozoic Era ◽  
The Common ◽  
Leaf Curl Virus ◽  
Search For Homologs

The begomoviruses (BGVs) are plant pathogens that evolved in the Old World during the Cretaceous and arrived to the New World (NW) in the Cenozoic era. A subgroup of NW BGVs, the “Squash leaf curl virus (SLCV) lineage” (S-Lin), includes viruses with unique characteristics. To get clues on the evolutionary origin of this lineage, a search for divergent members was undertaken. Four novel BGVs were characterized, including one that is basal to the group. Comparative analyses led to discover a ~670 bp genome module that is nearly exclusive of this lineage, encompassing the replication origin, the AC4 gene, and 480 bp of the Rep gene. A similar DNA module was found in two curtoviruses, hence suggesting that the S-Lin ancestor acquired its distinctive genomic segment by recombination with a curtovirus. This hypothesis was definitely disproved by an in-depth sequence analysis. The search for homologs of S-Lin Rep uncover the common origin of Rep proteins encoded by diverse Geminiviridae genera and viral “fossils” integrated at plant genomes. In contrast, no homolog of S-Lin Rep was found in public databases. Consequently, it was concluded that the SLCV clade ancestor evolved by a recombination event between a primitive NW BGV and a virus from a hitherto unknown lineage.

scholarly journals Squash Leaf Curl Virus: A New World Bipartite Begomovirus Threatening Squash Production in Oman

Plant Disease ◽  
2020 ◽  
Vol 104 (9) ◽  
pp. 2533-2533
Author(s):  
M. S. Shahid ◽  
H. Al-Sulaimani ◽  
A. M. Al-Sadi
Keyword(s):  
New World ◽  
Bipartite Begomovirus ◽  
Squash Leaf Curl Virus ◽  
Leaf Curl Virus ◽  
Leaf Curl

scholarly journals Introduction of the New World Squash leaf curl virus to Squash (Cucurbita pepo) in Egypt: A Potential Threat to Important Food Crops

Plant Disease ◽  
2006 ◽  
Vol 90 (9) ◽  
pp. 1262-1262 ◽  
Author(s):  
A. M. Idris ◽  
A. Abdel-Salam ◽  
J. K. Brown
Keyword(s):  
United States ◽  
New World ◽  
The United States ◽  
Pcr Analysis ◽  
Broad Host Range ◽  
Species Introduction ◽  
Crop Species ◽  
Squash Leaf Curl Virus ◽  
Leaf Curl Virus ◽  
Leaf Curl

Squash plants showing leaf curling, yellow mottling, and reduced fruit set were observed in fields in Giza, Egypt in spring 2005. These particular symptoms had not been observed previously in zucchini squash plants in Egypt, but were reminiscent of those caused by begomoviruses (Geminiviridae) that are known to occur in the region, including Watermelon chlorotic stunt virus. Squash plants were heavily infested with the whitefly Bemisia tabaci (Genn.), the only known vector of begomoviruses. Total nucleic acids were isolated from symptomatic squash leaves using the cetyltrimethylammoniumbromide method, and extracts were subjected to polymerase chain reaction (PCR) analysis using two sets of PCR primers. One primer set (prAV2644 and prAC1154) was designed to amplify a fragment that contains the entire viral coat protein (Cp), while the second primer set (prBV1855 and prBC656) was designed to amplify the common region (CR) of DNA-B of begomoviruses (1). The expected size fragments were cloned and the sequence was determined for five clones each. Unexpectedly, the Cp and the CR-B fragments shared their highest nucleotide sequence (nt) identity among well-characterized begomoviruses to the bipartite Squash leaf curl virus (SLCV) native to the western United States. A third primer set (prAC344 and prAV1134) (1) was subsequently used to amplify the remainder of the putative SLCV DNA-A. The fragment was cloned and the DNA sequence was determined. Assembly of the overlapping DNA-A fragments resulted in a complete DNA-A component sequence of 2,636 nt, which is identical to the expected size of the SLCV DNA-A component (GenBank Accession No. DQ285019). Comparison with the latter sequence indicated that the Egyptian squash isolate shared 98% nt identity with SLCV. The sequence for the DNA-B fragment (1,162 nt) shared 94% nt identity with SLCV and was deposited in GenBank as Accession No. DQ285020. The high-shared nt identity with SLCV (2) from the United States suggests that this isolate, herein SLCV-EG, has been introduced into Egypt. The relatively low DNA-B nt sequence identity was a not a surprise since this component is normally less conserved even between strains of a single begomoviral species. Introduction of SLCV is not only potentially significant to the domestic production of crop species in the Cucurbitaceae but also for legume crops. SLCV has a broad host range that also includes members of the Fabaceae, which includes species that contribute significant sources of protein for much of Egypt's population. The virus thus far is thought to be present only in Lower Egypt, however, it could feasibly threaten legume and cucurbit crops if it spreads to Upper Egypt. To our knowledge, this is the first begomovirus of New World origin to become established in the Old World. References: (1) A. M. Idris and J. K. Brown. Phytopathology 88:648, 1998. (2) S. G. Lazarowitz. Virology 180:70, 1991.

scholarly journals SINE Insertions in Cladistic Analyses and the Phylogenetic Affiliations of Tarsius bancanus to Other Primates

Genetics ◽  
2001 ◽  
Vol 157 (2) ◽  
pp. 777-784
Author(s):  
Jürgen Schmitz ◽  
Martina Ohme ◽  
Hans Zischler
Keyword(s):  
New World ◽  
World Monkey ◽  
Old World ◽  
Alu Elements ◽  
Alu Sequences ◽  
Short Interspersed Elements ◽  
Divergence Point ◽  
Tarsius Bancanus ◽  
Cladistic Analyses ◽  
The Common

Abstract Transpositions of Alu sequences, representing the most abundant primate short interspersed elements (SINE), were evaluated as molecular cladistic markers to analyze the phylogenetic affiliations among the primate infraorders. Altogether 118 human loci, containing intronic Alu elements, were PCR analyzed for the presence of Alu sequences at orthologous sites in each of two strepsirhine, New World and Old World monkey species, Tarsius bancanus, and a nonprimate outgroup. Fourteen size-polymorphic amplification patterns exhibited longer fragments for the anthropoids (New World and Old World monkeys) and T. bancanus whereas shorter fragments were detected for the strepsirhines and the outgroup. From these, subsequent sequence analyses revealed three Alu transpositions, which can be regarded as shared derived molecular characters linking tarsiers and anthropoid primates. Concerning the other loci, scenarios are represented in which different SINE transpositions occurred independently in the same intron on the lineages leading both to the common ancestor of anthropoids and to T. bancanus, albeit at different nucleotide positions. Our results demonstrate the efficiency and possible pitfalls of SINE transpositions used as molecular cladistic markers in tracing back a divergence point in primate evolution over 40 million years old. The three Alu insertions characterized underpin the monophyly of haplorhine primates (Anthropoidea and Tarsioidea) from a novel perspective.

scholarly journals Characterization of a Synergistic Interaction Between Two Cucurbit-Infecting Begomoviruses: Squash leaf curl virus and Watermelon chlorotic stunt virus

2011 ◽  
Vol 101 (2) ◽  
pp. 281-289 ◽  
Author(s):  
Tali Sufrin-Ringwald ◽  
Moshe Lapidot
Keyword(s):  
Eastern Mediterranean ◽  
Dual Infection ◽  
Synergistic Interaction ◽  
Bipartite Begomoviruses ◽  
Disease Symptoms ◽  
Squash Leaf Curl Virus ◽  
Effect On Yield ◽  
Leaf Curl Virus ◽  
Watermelon Chlorotic Stunt Virus ◽  
Leaf Curl

Squash leaf curl virus (SLCV) and Watermelon chlorotic stunt virus (WmCSV) are cucurbit-infecting bipartite begomoviruses. Both viruses are found in the eastern Mediterranean basin but the effects of dual infection of both viruses on melon (Cucumis melo L.) have not been described. ‘Arava’ melon plants were inoculated in the greenhouse, using whiteflies, with either SLCV, WmCSV, or both. Control plants were exposed to nonviruliferous whiteflies or not exposed at all. Following inoculation, plants were transplanted to a 50-mesh insect-proof nethouse and grown until fruit maturity. The experiment was performed in two melon-growing seasons: spring, transplant in May and harvest in July; and summer, transplant in August and harvest in October. Following inoculation, SLCV-infected melon plants showed mild symptoms that disappeared with time, and there was no effect on plant height. WmCSV-infected plants developed disease symptoms that became more obvious with time, and plants were somewhat shorter than control plants in the spring but not in the summer. SLCV had no effect on yield, regardless of season. WmCSV had no statistically significant effect on yield in the spring but, in the summer, reduced yield by 22%, on average. Dual-inoculated plants showed a synergistic interaction between the two viruses. They developed disease symptoms that were more pronounced than WmCSV alone, with plants being shorter than control plants by 20 to 25% regardless of season. Moreover, the yield of dual-inoculated plants was reduced on average by 21% in the spring and 54% in the summer, and fruit appearance was adversely affected. Dual inoculation did not affect WmCSV DNA level but SLCV DNA level was increased several-fold by the presence of WmCSV.

scholarly journals Multiple Introductions of the Old World Begomovirus Tomato yellow leaf curl virus into the New World

2007 ◽  
Vol 73 (21) ◽  
pp. 7114-7117 ◽  
Author(s):  
Siobain Duffy ◽  
Edward C. Holmes
Keyword(s):  
North America ◽  
New World ◽  
Tomato Yellow Leaf ◽  
Yellow Leaf ◽  
Old World ◽  
Multiple Introductions ◽  
The Caribbean ◽  
Genomic Regions ◽  
Leaf Curl Virus ◽  
Leaf Curl

ABSTRACT A phylogenetic analysis of three genomic regions revealed that Tomato yellow leaf curl virus (TYLCV) from western North America is distinct from TYLCV isolated in eastern North America and the Caribbean. This analysis supports a second introduction of this Old World begomovirus into the New World, most likely from Asia.

scholarly journals Cucurbit leaf curl virus, a New Whitefly Transmitted Geminivirus in Arizona, Texas, and Mexico

Plant Disease ◽  
2000 ◽  
Vol 84 (7) ◽  
pp. 809-809 ◽  
Author(s):  
J. K. Brown ◽  
A. M. Idris ◽  
M. W. Olsen ◽  
M. E. Miller ◽  
T. Isakeit ◽  
...  
Keyword(s):  
Binding Site ◽  
Field Isolate ◽  
Bipartite Begomovirus ◽  
Degenerate Primers ◽  
Field Isolates ◽  
Squash Leaf Curl Virus ◽  
Cp Gene ◽  
Honeydew Melon ◽  
Leaf Curl Virus ◽  
Leaf Curl

In 1998 to 1999, geminivirus-like symptoms were observed in whitefly-infested pumpkin, honeydew melon, and muskmelon in Arizona and Texas and in Coahuilla, Mexico (MX), respectively. Plants exhibited leaf curl and/or mottling, reminiscent of symptoms caused by Squash leaf curl virus (SLCV-WAZ) described from Arizona in 1981 (2). The isolate from Arizona pumpkin fields was experimentally transmitted to pumpkin seedlings by the “B type” of Bemisia tabaci (Genn.), and symptoms were indistinguishable from those observed in infected fields. Samples from AZ, MX, and TX were assessed for begomovirus presence by polymerase chain reaction (PCR) using degenerate primers that amplify a contiguous fragment containing the viral coat protein (Cp) gene and common region (CR) of the A component (CR-A) (~2,100 bp) and a fragment containing the CR of the B component (CR-B) (~1,100 bp). One to four isolates from each location were examined by PCR using both primer pairs, and at least three amplicons per isolate were cloned and their sequences determined. Alignment of viral Cp nucleotide (nt) sequences revealed that AZ [AF256199], MX, and TX field isolates shared 98.7 to 100% sequence identity, but were only 84.5 to 85.6% identical to the Cp gene of SLCV-extended (SLCV-E) [M38183] and SLCV-restricted (SLCV-R) (S. G. Lazarowitz, unpublished), respectively, suggesting a new, previously undescribed begomoviral species (3). Further, the Cp nt sequence of the three field isolates was 6 nt shorter than SLCV-E, SLCV-WAZ [AF256203], and SLCV-R Cp sequences. The CR-A [AF256200] and CR-B [AF256201] sequences (179 nt, each) of field isolates, including the theoretical Rep binding element, GGTGT, were 100% identical. Although the Rep binding site is identical among field isolates, SLCV-E, SLCV-R, and SLCV-WAZ, the field isolate CR sequence shared only 64.2, 67.5, and 66.9% overall identity with CR-A SLCV-E, SLCV-R [M63155], and SLCV-WAZ [AF256202], respectively. Prior to 1998 to 1999, SLCV-WAZ was the only New World begomovirus of cucurbits known to infect both melon (Cucumis) and pumpkin (Cucurbita) (1). Therefore, SLCV was initially suspected as the causal agent. However, here we provide evidence for a new, previously undescribed bipartite begomovirus of cucurbits in AZ, MX, and TX that is herein provisionally designated Cucurbit leaf curl virus (CuLCV). Prediction of its closest begomovirus relatives by Cp nt sequence and Rep binding site comparisons suggest that CuLCV is a new member of the SLCV lineage, also containing Bean calico mosaic virus, Cabbage leaf curl virus, SLCV-E, and Texas pepper virus-TAM. References: (1) J. K. Brown and M. R. Nelson. Phytopathology 74:1136, 1984. (2) J. K. Brown and M. R. Nelson. Ann. Appl. Biol. 115:243, 1986. (3) M. A. Mayo and C. R. Pringle. J. Gen. Virol. 97:649, 1998.

scholarly journals Messianism and UFO Sightings as Counterfactual Strategies of Enchantment of the World

2018 ◽  
Vol 14 (1) ◽  
pp. 99-109
Author(s):  
Piotr Urbanowicz
Keyword(s):  
Technological Progress ◽  
New World ◽  
Industrial Revolution ◽  
World Order ◽  
Common Denominator ◽  
New World Order ◽  
The Social ◽  
The World ◽  
The Common

Summary In this text, I argue that there are numerous affinities between 19th century messianism and testimonies of UFO sightings, both of which I regarded as forms of secular millennialism. The common denominator for the comparison was Max Weber’s concept of “disenchantment of the world” in the wake of the Industrial Revolution which initiated the era of the dominance of rational thinking and technological progress. However, the period’s counterfactual narratives of enchantment did not repudiate technology as the source of all social and political evil—on the contrary, they variously redefined its function, imagining a possibility of a new world order. In this context, I analysed the social projects put forward by Polish Romantics in the first half of the 19th century, with emphasis on the role of technology as an agent of social change. Similarly, the imaginary technology described by UFO contactees often has a redemptive function and is supposed to bring solution to humanity’s most dangerous problems.

scholarly journals Maintenance of an Old World Betasatellite by a New World Helper Begomovirus and Possible Rapid Adaptation of the Betasatellite

2009 ◽  
Vol 83 (18) ◽  
pp. 9347-9355 ◽  
Author(s):  
Muhammad Shah Nawaz-ul-Rehman ◽  
Shahid Mansoor ◽  
Rob W. Briddon ◽  
Claude M. Fauquet
Keyword(s):  
New World ◽  
Cotton Leaf ◽  
Old World ◽  
Tropical Regions ◽  
Cabbage Leaf Curl Virus ◽  
Chili Leaf Curl Betasatellite ◽  
Serious Disease ◽  
Leaf Curl Virus ◽  
First Time ◽  
Leaf Curl

ABSTRACT Begomoviruses (family Geminiviridae) cause major losses to crops throughout the tropical regions of the world. Begomoviruses originating from the New World (NW) and the Old World (OW) are genetically distinct. Whereas the majority of OW begomoviruses have monopartite genomes and whereas most of these associate with a class of symptom-modulating satellites (known as betasatellites), the genomes of NW begomoviruses are exclusively bipartite and do not associate with satellites. Here, we show for the first time that a betasatellite (cotton leaf curl Multan betasatellite [CLCuMuB]) associated with a serious disease of cotton across southern Asia is capable of interacting with a NW begomovirus. In the presence of CLCuMuB, the symptoms of the NW cabbage leaf curl virus (CbLCuV) are enhanced in Nicotiana benthamiana. However, CbLCuV was unable to interact with a second betasatellite, chili leaf curl betasatellite. Although CbLCuV can transreplicate CLCuMuB, satellite accumulation levels in plants were low. However, progeny CLCuMuB isolated after just one round of infection with CbLCuV contained numerous mutations. Reinoculation of one such progeny CLCuMuB with CbLCuV to N. benthamiana yielded infections with significantly higher satellite DNA levels. This suggests that betasatellites can rapidly adapt for efficient transreplication by a new helper begomovirus, including begomoviruses originating from the NW. Although the precise mechanism of transreplication of betasatellites by begomoviruses remains unknown, an analysis of betasatellite mutants suggests that the sequence(s) required for maintenance of CLCuMuB by one of its cognate begomoviruses (cotton leaf curl Rajasthan virus) differs from the sequences required for maintenance by CbLCuV. The significance of these findings and, particularly, the threat that betasatellites pose to agriculture in the NW, are discussed.

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