Studies on Lagenophrys tattersalli sp. n. (Ciliata Peritricha, Vorticellinae) Part I. Structure, Asexual Reproduction and Metamorphosis

1942 ◽  
Vol s2-83 (330) ◽  
pp. 171-196
Author(s):  
A. G. WILLIS
Keyword(s):  
Life Cycle ◽  
Asexual Reproduction ◽  
Marginal Zone ◽  
De Novo ◽  
Contractile Vacuole ◽  
Cholesterol Esters ◽  
Marine Ciliate ◽  
Reserve Material ◽  
Diagnostic Characters ◽  
Superficial Area

1. The diagnostic characters of a new marine ciliate, Lagenophrys tattersalli, have been described. The lorica is chiefly distinguished by the possession of a ventral shelf, a clearly defined central cap and a marginal zone formed during metamorphosis. The adoral spiral of about two turns is distinguished by the possession of an undulating membrane. 2. The macronucleus consists of a chromatin network with a plastin component in the form of interspersed spherical plasmosomes. 3. Eeserve substances are present at certain stages of the life cycle in the form of spheres composed of mixtures of fats and h'poids (chiefly cholesterol and cholesterol esters). The reserve substances accumulate during the trophic period and reach their maximum abundance prior to division. 4. Asexual reproduction takes place by two types of division leading in each case to the separation of motile organisms or swarmers and non-motile residual organisms. 5. The swarmer is always provided with a considerable quantity of fatty and lipoid reserve material. This is derived by the equal or unequal partition of the reserve material of the parent. 6. The peristome and ciliary girdle of the swarmer are formed from the division of the peristome and adoral spiral, respectively, of the parent and do not arise de novo. 7. It is maintained that the ciliary girdle of L. tattersalli does not correspond to the true ventral cilia of forms like Trichodina. 8. The ciliary girdle of the swarmer is disposed around a cavity (the sucker cavity) which was originally continuous with the vestibule of the parent. The ciliary girdle and the contractile vacuole of the swarmer are associated with the sucker cavity in the same way as the adoral spiral and contractile vacuole of the parent are associated with the vestibule. 9. In metamorphosis the sucker cavity of the swarmer becomes distended, probably bj the secretion of fluid. This growth cavity, as it may be termed, increases the superficial area of the protoplasm until the dimensions of the adult lorica are attained. The marginal zone of the lorica is laid down at this period and the growth cavity afterwards decreases in size. The adoral spiral of the adult is formed from the ciliary girdle of the swarmer after the cilia of the latter have become absorbed. The growth cavity is absorbed into the vestibule. 10. The reserve materials of the swarmer are completely used up before the end of metamorphosis.

Divisional morphogenesis in the marine ciliate Holosticha warreni (Ciliophora: Hypotrichida)

2000 ◽  
Vol 80 (5) ◽  
pp. 785-788 ◽  
Author(s):  
Xiaozhong Hu ◽  
Weibo Song ◽  
Alan Warren
Keyword(s):  
Coastal Waters ◽  
De Novo ◽  
Cortical Development ◽  
Impregnation Method ◽  
Marine Ciliate ◽  
Group Type ◽  
Generation Mode ◽  
The One

The cortical development of the marine hypotrichous ciliate Holosticha warreni, found in coastal waters near Qingdao, China, was investigated using the protargol impregnation method. In the proter, disorganization of the parental adoral zone of membranelles and undulating membranes contributes to the formation of its oral primordia which replace the parental buccal apparatus completely. Cirral anlagen in both division parts derive from the breaking of primary primordia. Most midventral cirri join in the formation of these primordia which occurs de novo separately from the oral primordia. Each of the 11 to 13 oblique streaks divides into three segments (new cirri) while the last two anlagen produce four each. Two frontoterminal cirri derive from the posteriormost anlage. The marginal rows develop from the parental structure. The generation mode of dorsal kineties is of the ‘one group type’ without forming caudal cirri.

Taxonomic revision of Australian species of Atyoida Randall (Crustacea : Decapoda : Atyidae), the genera Atyoida and Atya Leach

1982 ◽  
Vol 33 (2) ◽  
pp. 343 ◽  
Author(s):  
MJ Smith ◽  
WD Williams
Keyword(s):  
Life Cycle ◽  
Morphological Variation ◽  
Hawaiian Islands ◽  
Taxonomic Revision ◽  
Diagnostic Characters ◽  
Australian Species ◽  
Life Cycle Strategy ◽  
Distinguishing Features ◽  
Pacific Area

A reconsideration of the diagnostic characters of Atya Leach and Atyoida Randall supports their generic separation. Accordingly, Atyoida is reinstated as a full genus of which the distinguishing features are slender third peraeopods with a relatively short merus, a tapering endopod in the male first pleopod and protandry. It includes three species, A. bisulcata Randall from the Hawaiian Islands, A. pilipes (Newport) widespread in the Indo-Pacific area, and A. striolata (McCulloch & McNeill) found only in Australia. A. striolata is fully redescribed. Morphological variation throughout its range is slight; no subspecies are distinguishable. It is suggested that larvae hatch in estuaries and that protandry is an adaptive life-cycle strategy.

Dodecaceria berkeleyi n.sp., a Polychaete (Family Cirrutulidae) from New Zealand

1971 ◽  
Vol 28 (10) ◽  
pp. 1437-1443 ◽  
Author(s):  
G. A. Knox
Keyword(s):  
New Species ◽  
New Zealand ◽  
Asexual Reproduction ◽  
Larval Stage ◽  
Diagnostic Characters ◽  
Polychaete Family ◽  
A New Species

The described species of the genus Dodecaceria are reviewed. Fourteen species are recognized and their diagnostic characters are given. A new species, Dodecaceria berkeleyi, is described from New Zealand where it is found boring in the shells of large gastropod molluscs. An outline is given of the nature of the skin pigments, which are similar to the arenicolochrome of lugworms. Asexual reproduction in the genus is reviewed, and an account is given of autotomy in D. berkeleyi, followed by regeneration to give rise to two individuals, a method of reproduction similar to that which occurs in the colonial tube builder Dodecaceria fistulicola. An advanced larval stage found in the burrows of D. berkeleyi is described.

scholarly journals Temporal Viral Genome-Protein Interactions Define Distinct Stages of Productive Herpesviral Infection

mBio ◽  
2018 ◽  
Vol 9 (4) ◽  
Author(s):  
Jill A. Dembowski ◽  
Neal A. DeLuca
Keyword(s):  
Life Cycle ◽  
Protein Interactions ◽  
Viral Genome ◽  
Isotope Labeling ◽  
De Novo ◽  
Affinity Purification ◽  
Human Pathogens ◽  
Host Proteins ◽  
Viral Dna ◽  
Hsv 1

ABSTRACTHerpesviruses utilize multiple mechanisms to redirect host proteins for use in viral processes and to avoid recognition and repression by the host. To investigate dynamic interactions between herpes simplex virus type 1 (HSV-1) DNA and viral and host proteins throughout infection, we developed an approach to identify proteins that associate with the infecting viral genome from nuclear entry through packaging. To accomplish this, virus stocks were prepared in the presence of ethynyl-modified nucleotides to enable covalent tagging of viral genomes after infection for analysis of viral genome-protein interactions by imaging or affinity purification. Affinity purification was combined with stable isotope labeling of amino acids in cell culture (SILAC) mass spectrometry to enable the distinction between proteins that were brought into the cell by the virus or expressed within the infected cell before or during infection. We found that input viral DNA progressed within 6 h through four temporal stages where the genomes sequentially (i) interacted with intrinsic antiviral and DNA damage response proteins, (ii) underwent a robust transcriptional switch mediated largely by ICP4, (iii) engaged in replication, repair, and continued transcription, and then (iv) transitioned to a more transcriptionally inert state engagingde novo-synthesized viral structural components while maintaining interactions with replication proteins. Using a combination of genetic, imaging, and proteomic approaches, we provide a new and temporally compressed view of the HSV-1 life cycle based on input genome-proteome dynamics.IMPORTANCEHerpesviruses are highly prevalent and ubiquitous human pathogens. Studies of herpesviruses and other viruses have previously been limited by the ability to directly study events that occur on the viral DNA throughout infection. We present a new powerful approach, which allows for the temporal investigation of viral genome-protein interactions at all phases of infection. This work has integrated many results from previous studies with the discovery of novel factors potentially involved in viral infection that may represent new antiviral targets. In addition, the study provides a new view of the HSV-1 life cycle based on genome-proteome dynamics.

Splenic marginal zone lymphoma with a de novo t(8;14)(q24;q32) and a prolymphocytoid evolution responsive to rituximab-bendamustine

2018 ◽  
Vol 97 (10) ◽  
pp. 2001-2003
Author(s):  
Greta Scapinello ◽  
Marco Pizzi ◽  
Stefania Vio ◽  
Mitja Nabergoj ◽  
Andrea Visentin ◽  
...  
Keyword(s):  
Marginal Zone ◽  
De Novo ◽  
Marginal Zone Lymphoma ◽  
Splenic Marginal Zone Lymphoma

scholarly journals Observation of asexual reproduction with symbiont transmission in planktonic foraminifera

2020 ◽  
Vol 42 (4) ◽  
pp. 403-410 ◽  
Author(s):  
Haruka Takagi ◽  
Atsushi Kurasawa ◽  
Katsunori Kimoto
Keyword(s):  
Life Cycle ◽  
Sexual Reproduction ◽  
Vertical Transmission ◽  
Asexual Reproduction ◽  
Planktonic Foraminifera ◽  
Gamete Release ◽  
Symbiotic Algae ◽  
Laboratory Cultures ◽  
Symbiont Transmission

Abstract Gamete release has been frequently observed in laboratory cultures of various species of planktonic foraminifera. Those observations have been taken as evidence that these organisms produce new generations exclusively by sexual reproduction. We report here the first observation of asexual reproduction in Globigerinita uvula, a small, microperforate foraminifera. The asexual phase was associated with the release of ca. 110 offspring, all of which hosted symbiotic algae that must have been passed on directly from the parent. This event was also the first observation of vertical transmission of symbionts in planktonic foraminifera. Although the trigger of the observed asexual reproduction and its frequency in nature remain unknown, our observation indicates that among the planktonic foraminifera, at least G. uvula has not abandoned the asexual phase of its life cycle.

Redescription of the marine scuticociliate Glauconema trihymene Thompson, 1966 (Protozoa: Ciliophora): life cycle and stomatogenesis

Zootaxa ◽  
2006 ◽  
Vol 1296 (1) ◽  
pp. 1 ◽  
Author(s):  
HONGWEI MA ◽  
WEI B. SONG ◽  
ALAN WARREN ◽  
DAVID ROBERTS ◽  
JUN GONG ◽  
...  
Keyword(s):  
Life Cycle ◽  
Silver Nitrate ◽  
Major Part ◽  
Anterior Part ◽  
Posterior Part ◽  
Junior Synonym ◽  
Marine Ciliate ◽  
Frontal Plate ◽  
Protozoa Ciliophora

The transformation from trophont to tomite, morphology, and stomatogenesis during asexual division of the marine ciliate Glauconema trihymene Thompson, 1966 were studied using protargol and Chatton–Lwoff silver nitrate impregnation. An improved diagnosis for the genus Glauconema is suggested: Parauronematidae with polymorphic life cycle comprising trophont, tomite and cyst: buccal apparatus dimorphic, membranelles 1 and 2 closely opposed in trophont while well separated in tomite; paroral membrane uniform, extending anteriorly to midway of membranelle 2; single caudal cilium present; conspicuous glabrous frontal plate. Morphological redescription and stomatogenetic studies were made for G. trihymene. Stomatogenesis in G. trihymene is characterized by: paroral membrane and scutica in the opisthe originate from the anterior part of the parental paroral membrane; membranelles 1 and 2 in the opisthe derive from the posterior part of the parental paroral membrane; the major part of the proliferated scutica develops into membranelle 3 with only a small part comprising several kinetosomes joining in the formation of membranelle 2. Several stages of the transformation from trophont to tomite were also observed. This process starts from an anarchic field, which originates from the whole parental paroral membrane. These develop into two primordia that generate the paroral membrane and three new membranelles, respectively. The three parental membranelles are resorbed or join in the formation of the new membranelles, while the scutica is retained and does not take part in the transformation. The genus Urocryptum Pérez-Uz & Guinea, 2001 is considered a junior synonym of Glauconema and U. tortum is hence transferred to the genus Glauconema as G. tortum (Maupas, 1883) nov. comb.

scholarly journals The Development, Morphology and Budding of the Ascidian Diazona

1948 ◽  
Vol 27 (2) ◽  
pp. 389-399 ◽  
Author(s):  
N. J. Berrill
Keyword(s):  
Life Cycle ◽  
Asexual Reproduction ◽  
Basic Type ◽  
The Other ◽  
Strong Argument ◽  
Bud Formation ◽  
Present Account ◽  
The Family ◽  
The One ◽  
Complete Account

Diazona is represented in European waters only by Diazona violacea Savigny. It is a compound ascidian forming massive colonies of spectacular size and appearance. In many ways it is the most interesting of all ascidians, for in its adult structure it straddles two commonly accepted orders and in itself is a strong argument against such a division; it is the only oviparous and small egged compound ascidian, two features undoubtedly primitive; and its manner of budding is the simplest and probably is the basic type for the group as a whole. Only fragmentary descriptions of the morphology and reproduction exist, and a more or less complete account of the various stages of the life cycle may be of some value. The family Diazonidae includes, in addition to Diazona itself, the genera Tylobranchion of subantarctic regions, and Rhopalea of Mediterranean and northern waters. In its entirety Diazona appears to link with such divergent forms as Ciona on the one hand and Archidistoma on the other. The fact that Diazona is obtained by dredging in relatively swift offshore waters and lives poorly in an aquarium probably accounts for the existing unsatisfactory state of knowledge of most of its phases. Most of what is known concerns asexual reproduction; and attention has been given, at various times, primarily to the process of regeneration, rather than bud formation, for example by Della Valle (1884), Caullery (1914), Oka (1906) under the name Aphanobranchion, and by Salfi (1926).The material of the present account was collected at various times in the Plymouth area from the Mewstone and Eddystone grounds.

Aberrant Somatic Hypermutation in Extranodal Marginal Zone B-Cell Lymphoma of MALT Type.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 417-417 ◽  
Author(s):  
Alexander Deutsch ◽  
Ariane Aigelsreiter ◽  
Christine Beham-Schmid ◽  
Alfred Beham ◽  
Werner Linkesch ◽  
...  
Keyword(s):  
B Cell ◽  
Malt Lymphoma ◽  
Marginal Zone ◽  
De Novo ◽  
Cell Lymphoma ◽  
Somatic Hypermutation ◽  
B Cell Lymphoma ◽  
Chromosomal Translocations ◽  
Genome Wide ◽  
Balanced Translocations

Abstract Extranodal marginal zone B-cell lymphoma of mucosa associated lymphoid tissue (MALT lymphoma) accounts for approximately 7% to 8% of all non-Hodgkin lymphomas (NHLs) being the third most frequent histological subtype. The gastrointestinal tract - particularly the stomach - is the most common site of MALT lymphoma comprising 50% of all cases, but virtually every organ may be affected by this type of lymphoma. Transformation (or de novo emergence at extranodal sites) in diffuse large B-cell lymphoma (DLBCL) occurs but - according to the WHO criteria - is considered as separate entity. The understanding of the molecular biology of MALT lymphoma has significantly improved following the recent cloning of recurrent balanced translocations such as t(11;18) or t(14;18), but a mechanism for genome-wide instability during MALT lymphomagenesis has not been described. We have reported that the somatic hypermutation process (SHM) physiologically aimed at mutating the immunoglobulin variable gene (IgV) aberrantly targets multiple proto-oncogenes in >50% of DLCBL (Pasqualucci et al., Nature412:341, 2001). Consequently, multiple mutations are introduced in the 5′ region of genes including known proto-oncogenes such as PIM-1, PAX-5, Rho/TTF and c-MYC. To further investigate whether aberrant somatic hypermutation (ASHM) also occurs in MALT lymphoma, we studied the mutation profile of these genes in 17 MALT lymphomas (6 of gastric- and 11 of nongastric origin) and 18 extranodal DLBCL (10 gastric, 8 nongastric). Mutations in one or more genes were detected in 15 of 17 (88.2%) cases of MALT lymphoma and in all of 18 (100%) cases of extranodal DLBCL. 7 of 17 (41.2%) and 15 of 18 (83.3%) carried mutations in two or more genes in the MALT- and DLBC-lymphoma group, respectively. Overall, mutations in PIM-1 occurred in 5 of 17 (29.4%) cases with MALT lymphoma and in 10 of 18 (55.5%) in extranodal DLBCL cases. For PAX-5, the distribution of mutated cases between MALT- and DLBC-lymphoma was 6 of 17 (35.3%) and 10 of 18 (55.5%), for Rho/TTF 3 of 17 (17.6%) and 8 of 18 (44.4%) and for c-MYC 9 of 17 (52.9%) and 12 of 18 (66.6%), respectively. A total of 99 sequence variants were found in 35 cases, 29 in the MALT lymphomas and 70 in extranodal DLBCL. Although the mutations were almost exclusively single base pair substitutions (n=98 ), an insertion was also present (n=1). Mutations were of somatic origins, occur independent of chromosomal translocations to the Ig loci and share features of the IgV SHM process including bias for transition over transversion, preferential hotspot (RGYW/WRCY) targeting and restriction to the first 1–2Kb from the promoter. The mean mutation frequency in mutated MALT lymphomas was with 0.045 x10−2/bp 1.7 fold lower compared to 0.08 x10−2/bp in mutated extranodal DLBCL. Further in PIM-1, PAX-5 and c-MYC some of the mutations were found to affect coding exons, leading to amino acid exchanges, thus potentially altering gene function. These data indicate that aberrant SHM is associated with extranodal DLBCL and MALT lymphoma, likewise. By mutating regulatory and coding sequences of the targeted genes and by possibly favouring chromosomal translocations ASHM may represent a major contributor to their pathogenesis. ASHM may further support a model of MALT lymphomagenesis leading from an antigen driven lesion to transformed MALT lymphoma finally evolving to overt DLBCL.

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