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71.
Hilde Nybom 《Plant Systematics and Evolution》1986,152(3-4):211-218
A review of current knowledge of chromosome numbers and modes of reproduction in the genusRubus L. is presented. Chromosome numbers from some species of subg.Malachobatus
Focke together with results of crossing experiments are reported for the first time. 相似文献
72.
Caroline Geeraerts Michaël Ovidio Hilde Verbiest David Buysse Johan Coeck Claude Belpaire Jean-Claude Philippart 《Hydrobiologia》2007,582(1):143-153
Adult roach Rutilus rutilus (L.) (N = 24; 19.9–36.1 cm FL) from three highly fragmented Belgian rivers were tagged with surgically implanted radio transmitters.
Their seasonal movements were observed from March to August 2004 (circum reproduction period) in river stretches delimited
by two physical barriers. In the three rivers, roach displayed similar patterns of movements which were mainly influenced
by the date of observation (movements increased in late April–May) and water temperature (travel distances were more important
when water temperature ranged between 10°C and 14°C). Roach sometimes cleared physical obstacles. The mean distances travelled
in each river were relatively short (max. 2.5 km) and mainly influenced by the length of the study reach, which was delimited
by physical barriers. 相似文献
73.
Froyen G Bauters M Boyle J Van Esch H Govaerts K van Bokhoven H Ropers HH Moraine C Chelly J Fryns JP Marynen P Gecz J Turner G 《Human genetics》2007,121(5):539-547
Using high resolution X chromosome array-CGH we identified an interstitial microdeletion at Xp11.23 in three brothers with
moderate to severe mental retardation (MR) without dysmorphic features. The extent of the deletion was subsequently delineated
to about 50 kb by regular PCR and included only the SLC38A5 and FTSJ1 genes. The loss of the FTSJ1 MR gene in males is expected to result in the observed phenotype but the contribution of the deletion of the solute carrier
SLC38A5 gene is less clear. Their mother also carries the deletion and completely inactivates the aberrant X chromosome. Interestingly,
the distal breakpoint is situated within a 200 kb SSX repeat region that appears to stimulate recombination since subtle copy
number changes often occur at this location and it is frequently involved in translocations in tumours. Since this apparent
SSX unstable structure is flanked proximally by FTSJ1 and PQBP1, subtle deletions or duplications at this location would be expected to cause MR, as in our family. So far, we have screened
a cohort of 300 patients but did not find additional aberrations at the FTSJ1 locus indicating that the frequency is likely to be low. 相似文献
74.
Nickel is a cofactor for various microbial enzymes, yet as a trace element, its scavenging is challenging. In the case of the pathogen Helicobacter pylori, nickel is essential for the survival in the human stomach, because it is the cofactor of the important virulence factor urease. While nickel transport across the cytoplasmic membrane is accomplished by the nickel permease NixA, the mechanism by which nickel traverses the outer membrane (OM) of this Gram-negative bacterium is unknown. Import of iron-siderophores and cobalamin through the bacterial OM is carried out by specific receptors energized by the TonB/ExbB/ExbD machinery. In this study, we show for the first time that H. pylori utilizes TonB/ExbB/ExbD for nickel uptake in addition to iron acquisition. We have identified the nickel-regulated protein FrpB4, homologous to TonB-dependent proteins, as an OM receptor involved in nickel uptake. We demonstrate that ExbB/ExbD/TonB and FrpB4 deficient bacteria are unable to efficiently scavenge nickel at low pH. This condition mimics those encountered by H. pylori during stomach colonization, under which nickel supply and full urease activity are essential to combat acidity. We anticipate that this nickel scavenging system is not restricted to H. pylori, but will be represented more largely among Gram-negative bacteria. 相似文献
75.
Mala Isrie Martin Breuss Guoling Tian Andi?Harley Hansen Francesca Cristofoli Jasmin Morandell Zachari?A. Kupchinsky Alejandro Sifrim Celia?Maria Rodriguez-Rodriguez Elena?Porta Dapena Kurston Doonanco Norma Leonard Faten Tinsa Stéphanie Moortgat Hakan Ulucan Erkan Koparir Ender Karaca Nicholas Katsanis Valeria Marton Joris?Robert Vermeesch Erica?E. Davis Nicholas?J. Cowan David?Anthony Keays Hilde Van?Esch 《American journal of human genetics》2015,97(6):790-800
Circumferential skin creases Kunze type (CSC-KT) is a specific congenital entity with an unknown genetic cause. The disease phenotype comprises characteristic circumferential skin creases accompanied by intellectual disability, a cleft palate, short stature, and dysmorphic features. Here, we report that mutations in either MAPRE2 or TUBB underlie the genetic origin of this syndrome. MAPRE2 encodes a member of the microtubule end-binding family of proteins that bind to the guanosine triphosphate cap at growing microtubule plus ends, and TUBB encodes a β-tubulin isotype that is expressed abundantly in the developing brain. Functional analyses of the TUBB mutants show multiple defects in the chaperone-dependent tubulin heterodimer folding and assembly pathway that leads to a compromised yield of native heterodimers. The TUBB mutations also have an impact on microtubule dynamics. For MAPRE2, we show that the mutations result in enhanced MAPRE2 binding to microtubules, implying an increased dwell time at microtubule plus ends. Further, in vivo analysis of MAPRE2 mutations in a zebrafish model of craniofacial development shows that the variants most likely perturb the patterning of branchial arches, either through excessive activity (under a recessive paradigm) or through haploinsufficiency (dominant de novo paradigm). Taken together, our data add CSC-KT to the growing list of tubulinopathies and highlight how multiple inheritance paradigms can affect dosage-sensitive biological systems so as to result in the same clinical defect. 相似文献
76.
Hilde Nelissen Dominique Eeckhout Kirin Demuynck Geert Persiau Alan Walton Michiel van Bel Marieke Vervoort Jasper Candaele Jolien De Block Stijn Aesaert Mieke Van Lijsebettens Sofie Goormachtig Klaas Vandepoele Jelle Van Leene Michael Muszynski Kris Gevaert Dirk Inzé Geert De Jaeger 《The Plant cell》2015,27(6):1605-1619
Most molecular processes during plant development occur with a particular spatio-temporal specificity. Thus far, it has remained technically challenging to capture dynamic protein-protein interactions within a growing organ, where the interplay between cell division and cell expansion is instrumental. Here, we combined high-resolution sampling of the growing maize (Zea mays) leaf with tandem affinity purification followed by mass spectrometry. Our results indicate that the growth-regulating SWI/SNF chromatin remodeling complex associated with ANGUSTIFOLIA3 (AN3) was conserved within growing organs and between dicots and monocots. Moreover, we were able to demonstrate the dynamics of the AN3-interacting proteins within the growing leaf, since copurified GROWTH-REGULATING FACTORs (GRFs) varied throughout the growing leaf. Indeed, GRF1, GRF6, GRF7, GRF12, GRF15, and GRF17 were significantly enriched in the division zone of the growing leaf, while GRF4 and GRF10 levels were comparable between division zone and expansion zone in the growing leaf. These dynamics were also reflected at the mRNA and protein levels, indicating tight developmental regulation of the AN3-associated chromatin remodeling complex. In addition, the phenotypes of maize plants overexpressing miRNA396a-resistant GRF1 support a model proposing that distinct associations of the chromatin remodeling complex with specific GRFs tightly regulate the transition between cell division and cell expansion. Together, our data demonstrate that advancing from static to dynamic protein-protein interaction analysis in a growing organ adds insights in how developmental switches are regulated. 相似文献
77.
78.
Pivac N Knezević A Gornik O Pucić M Igl W Peeters H Crepel A Steyaert J Novokmet M Redzić I Nikolac M Hercigonja VN Curković KD Curković M Nedić G Muck-Seler D Borovecki F Rudan I Lauc G 《Molecular & cellular proteomics : MCP》2011,10(1):M110.004200
Over a half of all proteins are glycosylated, and their proper glycosylation is essential for normal function. Unfortunately, because of structural complexity of nonlinear branched glycans and the absence of genetic template for their synthesis, the knowledge about glycans is lagging significantly behind the knowledge about proteins or DNA. Using a recently developed quantitative high throughput glycan analysis method we quantified components of the plasma N-glycome in 99 children with attention-deficit hyperactivity disorder (ADHD), 81 child and 5 adults with autism spectrum disorder, and a total of 340 matching healthy controls. No changes in plasma glycome were found to associate with autism spectrum disorder, but several highly significant associations were observed with ADHD. Further structural analysis of plasma glycans revealed that ADHD is associated with increased antennary fucosylation of biantennary glycans and decreased levels of some complex glycans with three or four antennas. The design of this study prevented any functional conclusions about the observed associations, but specific differences in glycosylation appears to be strongly associated with ADHD and warrants further studies in this direction. 相似文献
79.
Larsen HS Aure MH Peters SB Larsen M Messelt EB Kanli Galtung H 《Journal of molecular histology》2011,42(1):71-81
Aquaporin 5 (AQP5) is known to be central for salivary fluid secretion. A study of the temporal-spatial distribution of AQP5
during submandibular gland (SMG) development and in adult tissues might offer further clues to its unknown role during development.
In the present work, SMGs from embryonic day (E) 14.5–18.5 and postnatal days (P) 0, 2, 5, 25, and 60 were immunostained for
AQP5 and analyzed using light microscopy. Additional confocal and transmission electron microscopy were performed on P60 glands.
Our results show that AQP5 expression first occurs in a scattered pattern in the late canalicular stage and becomes more prominent
and organized in the terminal tubuli/pro-acinar cells towards birth. Additional apical membrane staining in the entire intralobular
duct is found just prior to birth. During postnatal development, AQP5 is expressed in both the luminal and lateral membrane
of pro-acinar/acinar cells. AQP5 is also detected in the basal membrane of acinar cells at P25 and P60. In the intercalated
ducts at P60, the male glands show apical staining in the entire segment, while only the proximal region is positive in the
female glands. These results demonstrate an evolving distribution of AQP5 during pre- and postnatal development in the mouse
SMGs. 相似文献
80.
Andrew M. Griffiths David W. Sims Andrew Johnson Arve Lynghammar Matthew McHugh Torkild Bakken Martin J. Genner 《Conservation Genetics》2011,12(2):577-582
Sequencing of a partial region of the mitochondrial control region has revealed no shared haplotypes between longnose skate (Dipturus oxyrinchus L.) sampled in the north-eastern Atlantic (Norway and Rockall) and those sampled in the Mediterranean (Mallorca). Bayesian estimation of the migration rate suggests little, if any, gene flow occurs between the regions and that the populations separated 20,000?years ago. These conclusions provide a genetic basis for long-standing observations, based on egg capsule and adult size, that longnose skate in the Mediterranean may be genetically isolated from other stocks. This result has important conservation implications for the threatened longnose skate. 相似文献