scholarly journals Maturyoshka: a maturase inside a maturase, and other peculiarities of the novel chloroplast genomes of marine euglenophytes

2021 ◽  
Author(s):  
Kacper Maciszewski ◽  
Nadja Dabbagh ◽  
Angelika Preisfeld ◽  
Anna Karnkowska
Keyword(s):  
Essential Gene ◽  
Functional Domains ◽  
The Novel ◽  
Patchy Distribution ◽  
Organellar Genomes ◽  
Green Algal ◽  
Plastid Genomes ◽  
Chloroplast Genomes ◽  
History Of ◽  
Eventual Loss

Organellar genomes often carry group II introns, which occasionally encode proteins called maturases that are important for splicing. The number of introns varies substantially among various organellar genomes, and bursts of introns have been observed in multiple eukaryotic lineages, including euglenophytes, with more than 100 introns in their plastid genomes. To examine the evolutionary diversity and history of maturases, an essential gene family among euglenophytes, we searched for their homologs in newly sequenced and published plastid genomes representing all major euglenophytes' lineages. We found that maturase content in plastid genomes has a patchy distribution, with a maximum of eight of them present in Eutreptiella eupharyngea. The most basal lineages of euglenophytes, Eutreptiales, share the highest number of maturases, but the lowest number of introns. We also identified a peculiar convoluted structure of a gene located in an intron, in a gene within an intron, within yet another gene, present in some Eutreptiales. Further investigation of functional domains of identified maturases shown that most of them lost at least one of the functional domains, which implies that the patchy maturase distribution is due to frequent inactivation and eventual loss over time. Finally, we identified the diversified evolutionary origin of analysed maturases, which were acquired along with the green algal plastid or horizontally transferred. These findings indicate that euglenophytes' plastid maturases have experienced a surprisingly dynamic history due to gains from diversified donors, their retention, and loss.

scholarly journals A new lineage of non-photosynthetic green algae with extreme organellar genomes

2021 ◽  
Author(s):  
Tomáš Pánek ◽  
Dovilė Barcytė ◽  
Sebastian C. Treitli ◽  
Kristína Záhonová ◽  
Martin Sokol ◽  
...  
Keyword(s):  
Mitochondrial Genome ◽  
Genome Evolution ◽  
Transcriptome Assembly ◽  
Molecular Characteristics ◽  
Functional Link ◽  
Coding Regions ◽  
Organellar Genome ◽  
Organellar Genomes ◽  
Green Algal ◽  
Plastid Genomes

Background: The plastid genomes of the green algal order Chlamydomonadales tend to expand their non-coding regions, but this phenomenon is poorly understood. Here we shed new light on organellar genome evolution in Chlamydomonadales by studying a previously unknown non-photosynthetic lineage. We established cultures of two new Polytoma-like flagellates, defined their basic characteristics and phylogenetic position, and obtained complete organellar genome sequences and a transcriptome assembly for one of them. Results: We discovered a novel deeply diverged chlamydomonadalean lineage that has no close photosynthetic relatives and represents an independent case of photosynthesis loss. To accommodate these organisms, we establish a new genus, Leontynka, with two species L. pallida and L. elongata distinguished by both morphological and molecular characteristics. Notable features of the colourless plastid of L. pallida deduced from the plastid genome (plastome) sequence and transcriptome assembly include the retention of ATP synthase, thylakoid-associated proteins, carotenoid biosynthesis pathway, and plastoquinone-based electron transport chain, the latter two modules having an obvious functional link to the eyespot present in Leontynka. Most strikingly, the L. pallida plastome with its ~362 kbp is by far the largest among non-photosynthetic eukaryotes investigated to date. Instead of a high gene content, its size reflects extreme proliferation of sequence repeats. These are present also in coding sequences, with one repeat type found in exons of 11 out of 34 protein-coding genes and up to 36 copies per gene, affecting thus the encoded proteins. The mitochondrial genome of L. pallida is likewise exceptionally large, with its >104 kbp surpassed only by the mitogenome of Haematococcus lacustris among all members of Chlamydomonadales studied so far. It is also bloated with repeats, yet completely different from those in the L. pallida plastome, which contrasts with the situation in H. lacustris where both organellar genomes have accumulated related repeats. Furthermore, the L. pallida mitogenome exhibits an extremely high GC content in both coding and non-coding regions and, strikingly, a high number of predicted G-quadruplexes. Conclusions: With the unprecedented combination of plastid and mitochondrial genome characteristics, Leontynka pushes the frontiers of organellar genome diversity and becomes an interesting model for studying organellar genome evolution.

“What Freedom?”

2019 ◽  
Vol 74 (3) ◽  
pp. 305-331
Author(s):  
John Owen Havard
Keyword(s):  
South America ◽  
French Revolution ◽  
The Political ◽  
The Novel ◽  
Free Condition ◽  
Narrative Design ◽  
Economic Liberalism ◽  
History Of ◽  
Ways Of Thinking ◽  
John Owen

John Owen Havard, “‘What Freedom?’: Frankenstein, Anti-Occidentalism, and English Liberty” (pp. 305–331) “If he were vanquished,” Victor Frankenstein states of his monstrous creation in Mary Shelley’s Frankenstein (1818), “I should be a free man.” But he goes on: “Alas! what freedom? such as the peasant enjoys when his family have been massacred before his eyes, his cottage burnt, his lands laid waste, and he is turned adrift, homeless, pennyless, and alone, but free.” Victor’s circumstances approximate the deracinated subject of an emergent economic liberalism, while looking to other destitute and shipwrecked heroes. Yet the ironic “freedom” described here carries an added charge, which Victor underscores when he concludes this account of his ravaged condition: “Such would be my liberty.” This essay revisits the geographic plotting of Frankenstein: the digression to the East in the nested “harem” episode, the voyage to England, the neglected episode of Victor’s imprisonment in Ireland, and the creature’s desire to live in South America. Locating Victor’s concluding appeal to his “free” condition within the novel’s expansive geography amplifies the political stakes of his downfall, calling attention to not only his own suffering but the wider trail of destruction left in his wake. Where existing critical accounts have emphasized the French Revolution and its violent aftermath, this obscures the novel’s pointed critique of a deep and tangled history of English liberty and its destructive legacies. Reexamining the novel’s geography in tandem with its use of form similarly allows us to rethink the overarching narrative design of Frankenstein, in ways that disrupt, if not more radically dislocate, existing rigid ways of thinking about the novel.

Reading Statelessness

2018 ◽  
Author(s):  
Lyndsey Stonebridge
Keyword(s):  
Human Rights ◽  
Political Theory ◽  
The Novel ◽  
History Of The Novel ◽  
Political Sovereignty ◽  
History Of

Hannah Arendt’s analysis of the failure of human rights to address statelessness is well known. Less commented upon is how important literature was to her thought. This chapter shows how Arendt’s 1940s essays on Kafka connect the history of the novel to shifting definitions of legal and political sovereignty. Arendt reads The Castle as a blueprint for a political theory that is also a theory of fiction: in the novel K, the unwanted stranger, demolishes the fiction of the rights of man, and with it, the fantasy of assimilation. In a parallel move, Kafka also refuses to assimilate his character into the conventions of fiction. Arendt’s reading changes the terms for how we might approach the literature of exile and of human rights.

V.S. Naipaul, Caribbean Writing, and Caribbean Thought

2020 ◽  
Author(s):  
William Ghosh
Keyword(s):  
Intellectual Development ◽  
Public Intellectual ◽  
Historical Narrative ◽  
Derek Walcott ◽  
The Novel ◽  
Kamau Brathwaite ◽  
Political Debates ◽  
History Of ◽  
Principal Subject ◽  
Intellectual Formation

This book presents a new portrait of V.S. Naipaul, one of the twentieth-century’s most controversial writers about colonialism and its aftermath, by looking at his relationship with the Caribbean, the region of his birth. It argues that whilst Naipaul presented himself as a global public intellectual—a citizen of nowhere—his writing and thought was shaped by his Caribbean intellectual formation, and his investment in Caribbean political debates. Focusing on three key forms of Caribbean writing—the novel, the historical narrative, and the travel narrative—it shows how the generic, stylistic, and formal choices of writers had great political significance. Telling the story of his creative and intellectual development at three crucial points in Naipaul’s career, it offers a new intellectual biography of its principal subject. By showing Naipaul’s crucial place in the history of Caribbean ideas, it also provides new perspectives on a number of major writers and thinkers from the region, including C.L.R. James, Eric Williams, Kamau Brathwaite, Sylvia Wynter, George Lamming, Derek Walcott, Maryse Condé, and David Scott.

The Oxford History of the Novel in English

2018 ◽  
Keyword(s):  
World War Ii ◽  
English Language ◽  
Book History ◽  
World Order ◽  
The United States ◽  
The Novel ◽  
History Of The Novel ◽  
Post Colonial ◽  
The World ◽  
History Of

Volume Nine of this series traces the development of the ‘world novel’, that is, English-language novels written throughout the world, beyond Britain, Ireland, and the United States. Focusing on the period up to 1950, the volume contains survey chapters and chapters on major writers, as well as chapters on book history, publishing, and the critical contexts of the work discussed. The text covers periods from renaissance literary imaginings of exotic parts of the world like Oceania, through fiction embodying the ideology and conventions of empire, to the emergence of settler nationalist and Indigenous movements and, finally, the assimilations of modernism at the beginnings of the post-imperial world order. The book, then, contains chapters on the development of the non-metropolitan novel throughout the British world from the eighteenth to the mid twentieth centuries. This is the period of empire and resistance to empire, of settler confidence giving way to doubt, and of the rise of indigenous and post-colonial nationalisms that would shape the world after World War II.

Restoration Theatre and the Novel

2018 ◽  
Author(s):  
Jenny Davidson
Keyword(s):  
Eighteenth Century ◽  
Literary Form ◽  
The Novel ◽  
Cultural Transition ◽  
Strong Affinity ◽  
History Of ◽  
Restoration Theatre ◽  
Restoration Comedy ◽  
London Stage

This chapter explores the broad cultural transition from drama to novel during the Restoration period, which triggered one of the most productive periods in the history of the London stage. However, when it comes to the eighteenth century proper, the novel is more likely to be identified as the century's most significant and appealing popular genre. The chapter considers why the novel has largely superseded drama as the literary form to which ambitious and imaginative literary types without a strong affinity for verse writing would by default have turned their attention and energies by the middle of the eighteenth century. Something important may have been lost in the broad cultural transition from drama to novel. This chapter, however, contends that many things were preserved: that the novel was able to absorb many of the functions and techniques not just of Restoration comedy but of the theatre more generally.

An Essay on the Origins of the Novel

2018 ◽  
Author(s):  
Tim Whitmarsh
Keyword(s):  
Single Point ◽  
The Novel ◽  
History Of ◽  
History Of Scholarship

This chapter discusses the history of scholarship trying to trace the origins of the novel, and the impossibility of attempting to pin down a single point of origination.

Tom Jones

2008 ◽  
Author(s):  
Henry Fielding
Keyword(s):  
Eighteenth Century ◽  
Public Sphere ◽  
The Novel ◽  
Fourth Edition ◽  
Tom Jones ◽  
History Of

Fielding's comic masterpiece of 1749 was immediately attacked as `A motley history of bastardism, fornication, and adultery'. Indeed, his populous novel overflows with a marvellous assortment of prudes, whores, libertines, bumpkins, misanthropes, hypocrites, scoundrels, virgins, and all too fallible humanitarians. At the centre of one of the most ingenious plots in English fiction stands a hero whose actions were, in 1749, as shocking as they are funny today. Expelled from Mr Allworthy's country estate for his wild temper and sexual conquests, the good-hearted foundling Tom Jones loses his money, joins the army, and pursues his beloved across Britain to London, where he becomes a kept lover and confronts the possibility of incest. Tom Jones is rightly regarded as Fielding's greatest work, and one of the first and most influential of English novels. This carefully modernized edition is based on Fielding's emended fourth edition text and offers the most thorough notes, maps, and bibliography. The introduction uses the latest scholarship to examine how Tom Jones exemplifies the role of the novel in the emerging eighteenth-century public sphere.

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