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Natalizumab is a well-established disease-modifying therapy used in active multiple sclerosis (MS). The most serious adverse event is progressive multifocal leukoencephalopathy. For safety reasons, hospital implementation is mandatory. The SARS-CoV-2 pandemic has deeply affected hospital practices leading French authorities to temporarily authorize to administer the treatment at home. The safety of natalizumab home administration should be assessed to allow ongoing home infusion. The aim of the study is to describe the procedure and assess the safety in a home infusion natalizumab model. Patients presenting relapsing-remitting MS treated by natalizumab for over two years, non-exposed to John Cunningham Virus (JCV) and living in the Lille area (France) were included from July 2020 to February 2021 to receive natalizumab infusion at home every four weeks for 12 months. Teleconsultation occurrence, infusion occurrence, infusion cancelling, JCV risk management, annual MRI completion were analyzed. The number of teleconsultations allowing infusion was 365 (37 patients included in the analysis), all home infusions were preceded by a teleconsultation. Nine patients did not complete the one-year home infusion follow-up. Two teleconsultations canceled infusions. Two teleconsultations led to a hospital visit to assess a potential relapse. No severe adverse event was reported. All 28 patients who have completed the follow-up benefited from biannual hospital examination and JCV serologies and annual MRI. Our results suggested that the established home natalizumab procedure was safe using the university hospital home-care department. However, the procedure should be evaluated using home-based services outside the university hospital.

AbstractThe pea leaf weevil, Sitona lineatus(Linnaeus) (Coleoptera: Curculionidae), is an important pest of field peas, Pisum sativumLinnaeus (Fabaceae), and faba beans, Vicia fabaLinnaeus (Fabaceae), that has recently become established in the Prairie Provinces of Canada. Male pea leaf weevils produce an aggregation pheromone, 4-methyl-3,5-heptanedione, in the spring when overwintered weevils migrate to fields to feed and mate. The current study tests the attractiveness of the aggregation pheromone with and without synthetic bean volatiles to pea leaf weevils in the spring and in the fall when weevils seek perennial legumes to feed and overwinter. Modified Leggett traps similar to those used in Europe did not retain weevils in this study. Aggregation pheromone-baited pitfall traps caught male and female weevils in the spring and fall. Weevils were not attracted to traps baited with three bean volatiles, (Z)-3-hexen-1-yl acetate, (Z)-3-hexen-1-ol, and linalool. Bean volatiles did enhance response to pheromone, but only in the fall. Weevils were captured in most semiochemical-baited traps in a 1:1 sex ratio, but female-biased catch in control traps might indicate greater activity of females in the trap vicinity. This study lays the groundwork for semiochemical-based monitoring to detect pea leaf weevil spread in the Prairie Provinces.

Major space agencies have an increasing interest in highly accurate (200 m) autonomous landing on the Moon. Inertial-only navigation is not compatible with this challenging requirement. The techniques currently investigated rely on vision-based navigation. A first approach consists in tracking features between sequences of images in order to measure the angular rate as well as the direction of the velocity vector of the spacecraft. A second approach aims at identifying image features using a geo-referenced on-board database to determine the attitude and the position of the spacecraft. However, existing algorithms are computationally prohibitive and have a limited robustness to varying illumination conditions and surface characteristics. This paper presents the development of an innovative autonomous vision-based navigation system addressing these problems. Numerical simulations have shown that this system is capable of estimating the position and velocity of the vehicle with an accuracy better than 100 m and 0.1 m/s respectively. This work is the result of a successful collaboration between the Université de Sherbrooke, NGC Aerospace Ltd., Thales Alenia Space and the European Space Agency. The proposed system has been selected as the main navigation algorithm in three major research and development projects sponsored by European Space Agency and the Canadian Space Agency.

The PRoject for On-Board Autonomy (PROBA) is an ESA technology-demonstration program aimed at the in-orbit validation of autonomy-enabling space technologies. Following the success of PROBA-1, the PROBA-2 spacecraft was launched on 2 November 2009 and continues the in-flight demonstration of on-board autonomy by performing a Sun observation mission as well as numerous flight experiments. This paper completes previously published articles by presenting the in-flight results of two innovative autonomous GNC functions: (1) Star Tracker Earth Exclusion Angle Prediction for Earth avoidance and (2) Large-Angle Rotation around Fixed Axis. Finally, flight results of the Attitude and Orbit Control System (AOCS) nominal operation using these innovative GNC functions will be presented.

AbstractThe North American species of BrachylomiaHampson, 1906 are revised and four new species (B. cascadiasp. nov., B. obscurifasciasp. nov., B. pallidasp. nov., and B. sierrasp. nov.) are described. The monotypic genus LomilysisFranclemont, 1937 is synonymized with Brachylomia. Epunda onychinaGuen?e, 1852, which is currently placed in Brachylomia, is reclassified as a senior synonym of Egira alternans(Walker, [1857]), but Epunda onychina, not being associated with any known species in more than 150 years, is treated as a nomen oblitum, so Egira alternansis a nomen protectumunder provisions of Article 23.9.2 of the International Code of Zoological Nomenclature. Adults and genitalia of Nearctic species of Brachylomiaare figured.

AbstractThe higher classification of the families of the Noctuoidea with a quadrifid forewing (Nolidae, Strepsimanidae, Arctiidae, Lymantriidae, Erebidae, and Noctuidae) is reviewed from the perspective of recent classifications and the distribution of derived character states. On the basis of recent morphological and molecular studies, we propose a more inclusive definition of the family Noctuidae that adds the subfamilies Nolinae, Strepsimaninae, Arctiinae, Lymantriinae, and Erebinae to the subfamilies more traditionally included in the Noctuidae. Consequently, the superfamily Noctuoidea comprises the families Oenosandridae, Doidae, Notodontidae, Micronoctuidae, and Noctuidae. The tribe Cosmiini, currently in the subfamily Xyleninae, is downgraded to the status of subtribe Cosmiina and placed in the tribe Xylenini. The tribe Balsini, currently in the subfamily Xyleninae, is elevated to the status of subfamily Balsinae. The tribe Phosphilini is transferred from the subfamily Psaphidinae to the Xyleninae.

AbstractAlastriagen. nov.is described, and Callierges tropicalisSchaus is transferred to the genus. Alastria chicosp. nov.is described from western North America and Alastria machosp. nov.is described from Costa Rica. We provide illustrations of the adults and genitalia of all three species, as well as the male genitalia of two related genera, NedraClarke and ActinotiaH?bner.

AbstractThe species of the genus HyppaDuponchel are revised and a new species is described. Adults of all species are illustrated, as are male and female genitalia where known. A neotype is designated for Hadena ancocisconensisMorrison. The concept of Hyppa contrastais modified from that of a southern Appalachian endemic to that of a common transcontinental species.

AbstractThe North American species previously treated as Xanthia togata(Esper) is shown to be a distinct species and described as new. Illustrations of adults and genitalia of X. togataand Xanthia tatagoare provided.

AbstractThe North American species of the genus CosmiaOchsenheimer are reviewed and four species are recognized: Cosmia calami(Harvey), C. praeacuta(Smith) comb. nov., C. epipaschia(Grote) comb. nov., and C. elisaesp. nov.AchytonixMcDunnough syn. nov.is synonymized with Cosmiasubgenus CalymniaH?bner. Namangana praeacuta nigramaculataBarnes etBenjamin and Namangana praeacuta oraeBarnes etBenjamin are synonymized with Cosmia praeacuta. Illustrations of adults and genitalia are provided.

AbstractThe species of the LithophanelepidaGrote complex are reviewed and two new species of the genus LithophaneH?bner from western North America are described. Adults of all species are illustrated, as well as male and female genitalia (where known) and larva of L.lepidaand Lithophane itata(Smith). A key to species of the L. lepidagroup is provided.

AbstractThe name Neoligiagen.nov. is proposed for the ?Oligia? semicana(Walker) species group in North America and 12 species, N. rubirenasp.nov., N. pagosasp.nov., N. hardwickisp.nov., N. inermissp.nov., N. invenustasp.nov., N. albirenasp.nov., N. lanceasp.nov., N. elephassp.nov., N. lillooetsp.nov., N. surdirenasp.nov., N. canadensissp.nov.,and N. atlanticasp.nov. are described. Hadenella laevigataSmith is synonymized (synonymy restored) under Hadena tonsaGrote and Hadena haustaGrote is synonymized (synonymy restored) under Miana semicanaWalker. Adults of all species are illustrated as well as male and female genitalia, where known.

A cDNA clone encoding a proline-, threonine-, and glycine-rich protein (PTGRP) was isolated from a wild tomato species (Lycopersicon chilense) (L.X. Yu, H. Chamberland, J.G. Lafontain, Z. Tabaeizadeh [1996] Genome 39: 1185-1193). Northern-blot analysis and in situ hybridization studies revealed that PTGRP is down-regulated by drought stress. The level of the mRNA in leaves and stems of 8-d drought-stressed plants decreased 5- to 10-fold compared with that in regularly watered plants. The mRNA re-accumulated when drought-stressed plants were rewatered. Antibodies raised against a glutathione S-transferase/PTGRP fusion protein were used to elucidate the subcellular localization of the protein by immunogold labeling. In regularly watered L. chilense plants, PTGRP protein was found to be localized in xylem pit membranes and disintegrated primary walls. Examination of sections from drought-stressed plants revealed a significant decrease in the levels of labeling. In these samples, only a few scattered gold particles were detected in the same areas. In the leaf tissues of plants that had been rewatered for 3 d following an 8-d drought stress, the labeling pattern was similar to that of the regularly watered plants. To our knowledge, PTGRP is the first drought-regulated protein that has been precisely localized in the cell wall.

The distribution and fate of nuclei of the arbuscular-my-corrhizal fungus Gigaspora roseaduring late stages of axenic cultures were studied in fixed cultures by transmitted light, conventional and confocal laser scanning microscopy, and in live cultures with two-photon fluorescence microscopy. Mature specimens not yet showing apical septation displayed oval-shaped nuclei localized in lateral positions of the hypha all along the germ-tube length. Beside these, round-shaped nuclei were found to migrate along the central germ-tube core. Some (rare) germ-tube areas, delimited by septa and containing irregularly shaped, much brighter fluorescent nuclei were also found. Specimens that had just initiated the septation process after germ-tube growth arrest displayed round or oval-shaped nuclei in several portions of the germ tubes. These hyphal areas often alternated with other septa-delimited cytoplasmic clusters which contained distorted, brightly fluorescent nuclei. Completely septated specimens mostly lacked nuclei along their germ tubes. However, highly fluorescent chromatin masses appeared within remnants of cytoplasmic material, often compressed between close septa. Our results provide a first clear picture of the in vivo distribution of nuclei along arbuscular mycorrhizal fungal germ tubes issued from resting spores, and suggest that selective areas of their coenocytic hyphae are under specific, single nuclear control. They indicate as well that random autolytic processes occur along senescing G. roseagerm tubes, probably as a consequence of the absence of a host root signal for mycorrhizal formation. Finally, the data presented here allow us to envisage the fate of nuclei released by the germinating spore after nonsymbiotic fungal growth arrest.

Using two monoclonal antibodies, mAb Y12 and mAbK121, small nuclear ribonucleoproteins (snRNPs) were localized by immunofluorescence and immunogold electron microscopy in Pisum sativum and Cicer arietinum interphase nuclei. We showed that snRNPs were mostly found in nucleolus associated bodies (NABs) characterizing these two plant species. snRNPs were also found threoughout the nucleoplasm, their distribution being diffuse or speckled depending on the nucleus. Examination of optical sectins furnished by confocal laser microscopy allowed us to obtain more precise information on the number and location of NABs. One, two and rarely three (in green pea) of such structures were observed, their size varied from 0.8 to 1.5 µm and they were also systematically observed in intimate contact with the nucleolus. Under electron microscopy, labelling was likewise found to be noticeably higher over NABs than over the nucleoplasm. The possible relationship between NABs and other nuclear bodies found in animal cells and known to be involved in splicing of pre-mRNA is discussed.

Nucleolus-associated bodies (NABs) have long been noted in interphase nuclei of a wide variety of plant species. We have recently shown that these bodies consist largely of snRNPs and that they are located on the nucleolar surface in the immediate vicinity of the nucleolar organizer tracks. The present study revealed that, following exposure of roots to KCN, an agent that induces nucleolar segregation, NABs were intimately associated with intranucleolar chromatin. Although immunocytochemical tests with anti-DNA indicated that NABs contained no demonstrable amounts of DNA, our observations nevertheless add further support to the notion that these bodies are somehow related to the nucleolar chromosomes.

Nuclear DNA of rye (Secale cereale), a plant species with a relatively large genome (i.e., 18 pg diploid), has been characterized by determination of its content in repetitive sequences, buoyant density, and thermal denaturation properties. The reassociation kinetics of rye DNA reveals the presence of 70 to 75% repeated nucleotide sequences which are grouped into highly (Cot 1) and intermediately repetitive (Cot 1–100) fractions. On sedimentation in neutral CsCl gradients, native, high molecular weight DNA forms an almost symmetrical band of density 1.702 g/cm3. The highly repetitive DNA (Cot 1), on the other hand, is separated into two distinct peaks; the minor component has a density of 1.703 g/cm3 corresponding to that of a very rapidly reassociating fraction (Cot 0.01) which comprises 10 to 12% of the rye genome. The latter DNA contains segments which are repeated 6×105 to 6×106 times. The major peak of the Cot 1 fraction shows a density of 1.707 g/cm3 and consists of fragments repeated about 3.7×104 times. The intermediately repetitive DNA is much more heterogeneous than the Cot 1 fraction and has a low degree of repetition of the order of 8.5×102. The melting behavior of the Cot 1 fraction reveals the presence of a high degree of base pairing (i.e., 7% mismatching). When native rye DNA is resolved into fractions differing in GC content by hydroxyapatite thermal column chromatography and these fractions are analyzed for the presence of repetitive sequences, it is observed that the highly redundant DNA (Cot 1) is mostly located in the fraction denaturing between 80° and 90°C. This result suggests that highly repetitive rye DNA occurs in a portion of the genome which is neither very rich in AT nor in GC.

AbstractEighty-three butterfly species are credited to the fauna of the Yukon Territory, with an additional three deemed questionable. Species enumerated represent a compilation of both historic and current literature, and the records of collectors. The total includes previously unpublished records from the Canadian National Collection, but does not include unpublished records from any major museums in the United States. Approximately 30 collectors contributed field data.

The European Space Agency ESA is currently preparing the two deep space missions, Huygens and Rosetta. This paper reviews the related requirements for autonomous operations in a poorly known environment. While for Huygens emphasis is on the control of the descent through Titan's atmosphere, for Rosetta the safe drilling of material samples in the microgravity environment of a comet is analysed. The control concepts to enable adaptive reactions in an uncertain, remote environment are summarized for the crucial mission phases. The performance results obtained from computer simulations are presented and discussed.

The genomes of seven plant species belonging to the genus Allium and exhibiting a threefold variation in their nuclear DNA content were analyzed by studying their reassociation kinetics, equilibrium centrifugation behavior in neutral CsCl gradients, and melting properties. The reassociation kinetics experiments revealed the presence of 44–65% repeated DNA sequences. A comparison between DNA contents and the proportion of repeated DNA sequences indicated that, in Allium, increase in the genome size is not exclusively due to variations in the proportions of repetitive DNA. The total DNA as well as the various repetitive DNA fractions in all the Allium species examined exhibited, in spite of a few differences, a gross similarity in their behavior in neutral CsCl gradients and in their melting properties.

1. 125I-labelled (Asn1, Val5)-angiotensin II (125I-labelled AII) incubated with purified rat liver membranes was degraded with time, as estimated by three techniques: binding to an excess of specific antibody, polyacrylamide-gel electrophoresis and rebinding to fresh membranes. Degradation was inhibited in the presence of an excess of β1–24-corticotrophin but still very marked. 2. 125I-labelled AII became bound to purified rat liver membranes. Association and dissociation rates were slow. Binding was competitively inhibited by (Asn1, Val5)-AII, (Asp1, Ile5)-AII and (Des, Asn1, Ile5)-AII. Apparent KD was approximately 0·1 nmol/l. 3. Bound hormone was also partly degraded independently of time. 4. Angiotensinases inhibitors had different effects on 125I-labelled AII binding. A clear increase was observed in the presence of β1–24-corticotrophin and phenylmethylsulphonylfluoride whereas binding was decreased in the presence of EDTA or 8-hydroxyquinoline. 5. These results demonstrate the presence of high-affinity binding sites for AII and of angiotensinases in hepatic membranes.

The dingy cutworm is one of the more common and widely distributed of North American noctuids. Determination of the antennal responses of field-collected male moths to a standard test blend of pheromone components shows that two pheromonal phenotypes of the dingy cutworm occur throughout the prairie region of western Canada and at least two others occur in eastern Canada. The pheromone types are morphologically indistinguishable and, so far as is known, have similar life histories and biology. The two prairie types are broadly sympatric with partially overlapping seasonal flight periods. Although hybrids can be easily produced in the laboratory, there is no evidence of hybridization in the field. The pheromone system of the dingy cutworm is apparently rather plastic, resulting in a mosaic of pheromone types (sibling species) that appear to be reproductively isolated but have not differentiated morphologically.

AbstractThe comosagroup of the genus Euxoais defined on the basis of genital characters. The species in the group are: comosa(Morrison), lineifrons(Smith), guadalupensisnew species, lucidaBarnes and McDunnough, fumalis(Grote), and occidentalisnew species. On the basis of geographical variation of adults, life history data, and experimental hybridization, populations of E. comosaare arranged in five subspecies. Adults and genitalia are illustrated and a synopsis is given for each species and subspecies.

AbstractLaboratory and experimental studies of four of the five subspecies of Euxoa comosa(Morr.), i.e. annir, altera, lutulentaand Ontario, each formerly considered of specific rank, were undertaken to assess their taxonomic status. Morphologically the immature stages of the subspecies are similar although lutulentahas a 40–50% larger egg and the larvae of lutulentaand Ontarioare darker than those of annirand altera. The subspecies show differentiation in larval growth rate, number of larval instars, duration of preimaginal development and length of the preoviposition period. The possible adaptive significance of these differences are discussed. Hybrid F1were obtained from 11 of the 12 possible pairwise combinations. Eight of the F1hybrids were inbred and six produced fertile eggs. Some of the F2progenies exhibited a wide range of phenotypes encompassing all subspecies including those of the 5th subspecies, E. c. comosa. Although hybridization success was high there was some evidence of genetic incompatibility including dyssynchronous emergence of the sexes and the absence, shortage, or inviability of female moths in some crosses. Mating discrimination tests show a moderate level of mating bias between subspecies. Calling periods of females of the subspecies largely overlap although differences in the time at which calling begins might be responsible for some of the mating bias. Both laboratory and field tests of sex pheromone attraction indicate considerable sex pheromone specificity among the subspecies. The results are discussed with reference to a companion paper which on the basis of conventional taxonomic characters and biogeographic considerations concludes that Euxoa comosais best regarded as a polytypic species encompassing five subspecies.

AbstractThe biogeography of 171 North American species of Euxoa(Lepidoptera: Noctuidae) is reviewed. For biogeographical analysis, species are arranged in groups according to habitat; these are 62 aridland species, 69 forest species, 19 widespread species, and 21 species with special or unknown habitat requirements. Aridland species are distributed primarily in grassland areas in the Great Plains and in sagebrush areas or piñon–juniper woodland in the intermontane region. Ranges in these two regions are connected in arid corridors through the Rocky Mountain region. Forest species in western North America are arranged in two groups: those that occur in both conifer forests and piñon–juniper woodland (17 species), and those that occur only in conifer forests (40 species). Species in the former category occur throughout the mountain ranges of the west including those of the Great Basin wherever suitable habitat occurs. Those of the latter category occur in conifer forests on mountain ranges around the Great Basin but do not occur in the Great Basin, even in mountain ranges that support suitable habitat. Most forest species that occur in the Rocky Mountain region also occur in disjunct woodland areas in the Great Plains.The effect of Wisconsinan glaciation on the biogeographic regions of western North America is reconstructed from a review of fossil pollen and plant macrofossil studies. From this synthesis it is suggested that during the Wisconsinan glacial maximum, forest species were widely distributed in the Great Plains south of the Laurentian ice sheet, and at low elevations in the Sierra Nevada and Rocky Mountain regions. Piñon–juniper woodland species were widespread in the Great Plains. Forest species that do not occur in piñon–juniper woodland were distributed around the Great Basin but were prevented from reaching suitable habitat in mountain ranges within the Basin by unsuitable habitat in the intervening lowlands. The ranges of aridland species were greatly reduced during Wisconsinan time, particularly in the Great Plains. Aridland corridors through the Rocky Mountains were eliminated during the Wisconsinan glacial maximum.The possibility of speciation during Wisconsinan time is reviewed. Although the distribution of many sister-species are what would be expected from speciation during the Wisconsinan, the distributions may reflect allopatric distributions during Wisconsinan time and not speciation.

AbstractA blacklight trap was established at 3790 m in 1978 and at 3505 m, 3657 m, 3790 m, and 3810 m, in 1979, on the alpine tundra in Colorado. Weekly catches from 6 July to 4 August 1978, and 26 June to 14 September 1979, resulted in ca. 3500 individuals of over 48 species of moths. These results establish that a greater diversity of moths exists and greater nocturnal flight activity occurs than was previously supposed for alpine tundra communities. The implications for pollination and insect foraging are discussed.

AbstractEuxoa ustulatan. sp., allied to Euxoa perexcellens(Grote), is described from northern California. Adults and genitalia of both species are illustrated.

AbstractEuxoa melanan. sp., a sibling species of E. misturata(Smith), is described from the Panhandle area of Texas and from south-western Kansas. Together, the two species are herein referred to as the misturatagroup which is defined on the basis of genitalic characters. Adults and genitalia are illustrated.

AbstractThe immature stages of Euxoa basalis(Grote) are described and illustrated. Both the egg and pupa are similar to those of other Euxoaspecies and are virtually indistinguishable from some of them. The larva although morphologically quite similar to other Euxoalarvae is distinctive in coloration, particularly in the penultimate and ultimate stadia. Each of the larval instars is described; the ultimate instar in detail, the others briefly. A redescription of the adult is also given.

AbstractDiagnostic characters of Euxoa mimallonis(Grt.) and E. biformataSm. are discussed. Three species are described as new: conditafrom Forestville, Que., shastafrom northern California, and intermontanafrom the Great Basin and Colorado Plateau. Adults and genitalia of the species are illustrated and a key to species is included.

AbstractThe punctigeragroup of the genus Euxoais defined on the basis of genitalic characters. Species included in this group are Euxoa punctigera(Wlk.), E. spumataMcD., E. stigmatalis(Sm.), E. aurantiacan. sp., and E. canan. sp. Adults and genitalia of the species are illustrated and a key to species is included.

AbstractEuxoa antica, closely related to Euxoa terrena(Smith), is described from western United States. Adults and genitalia of both species are illustrated.

AbstractAn examination of the female genitalia of forms belonging to the redimiculacomplex of the genus Euxoadisclosed that the group consists of four species, redimicula(Morrison), servita(Smith), auripennisnew species, and arizonensisnew species. Diagnostic characters of the species in the group are discussed. A discriminant analysis was successfully used on characters of the male genitalia to segregate the males. A key to females and males of the species and subspecies of the redimiculagroup is included.

Summary Different concentrations of Nikkomycin Z, a competitive inhibitor of chitin-synthase, were applied to the arbuscular-mycorrhizal fungi (AMF)Gigaspora margarita andGlomus intraradices under in vitro conditions. These two fungi are known to differ in the structure and composition of their cell wall. The two AMF were able to grow in the presence of a higher concentration of this antibiotic than so far reported for other fungi. Fluorescence, electron microscopic and cytochemical studies showed that the blocking of the fungal chitin-synthase activity induces alterations in hyphal morphology, a reduction in fungal wall thickness, and several other changes in the hyphal wall structure and organization. The possible role of chitin-synthase in the hyphal growth and morphogenesis of these symbiotic fungi and its putative regulation by the host plant during the symbiosis are discussed.

Summary We describe the preparation of monoclonal antibodies to nuclear antigens in the green alga,Chlamydomonas reinhardtii, and their localization at the light and electron microscope level. Supernatants from hybridomas were screened by the ELISA method and the four antibodies giving the strongest signal were subjected to further analysis. At the LM level immunogold silver staining was used on semi-thick resinless sections. We have examined at the EM level the distribution of these antigens by post-embedding immunocytochemical techniques on sections of conventionally fixed specimens compared to cryofixed and freeze-substituted ones. Enhanced ultrastructural preservation was observed in cells which were cryofixed, freeze-substituted and embedded at -35°C in Lowicryl K4M. Different preparative procedures involving cryofixation and substitution are described. Of the four antibodies three were localized under light and electron microscopy. All three were distributed in the interchromatin space. One of these antigens (QUL4D2, 54 kDa) is also found in the dense fibrillar component and fibrillar centers of the nucleolus.