Topology of splicing and snRNP biogenesis in dinoflagellate nuclei

被引:11
作者
Alverca, Elsa
Franca, Susana
Diaz de la Espina, Susana Moreno
机构
[1] CSIC, E-28040 Madrid, Spain
[2] Inst Nacl Saude Dr Ricardo Jorge, P-1649016 Lisbon, Portugal
关键词
confocal microscopy; dinoflagellate; small nuclear ribonucleoprotein (snRNP); splicing; transmission electron microscopy;
D O I
10.1042/BC20050083
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Background information. Dinoflagellates are protists that are hypothesized to have experienced a secondary loss of histones. Amongst eukaryotes, they are unique in lacking these proteins. To date, information on the mechanisms involving remodelling, transcription and splicing of their chromatin is limited. Dinoflagellate genes lack TATA boxes and downstream polyadenylation sites and particular linear arrangements. They have an alpha-amanitin-sensitive RNA polymerase, specific transcription factors and regulators, and both transcriptional and post-transcriptional regulation of gene expression. Dinoflagellates produce either polycistronic or discrete mRNAs, and have conserved snRNAs (small nuclear RNAs), indicating that their genes are spliced. Results. Five representative dinoflagellate species (Amphidinium carterae, Akashiwo sanguinea, Alexandrium lusitanicum, Alexandrium fundyense and Prorocentrum micans), which show diversity in their DNA content, nuclear organization and taxonomic position, were investigated. The nuclear distribution and ultrastructural organization of splicing and snRNP (small nuclear ribonucleoprotein) biogenesis were determined by fluorescent and electron microscopy immunolabelling with Y12 sera [recognizing the sDMA (symmetrical dimethylarginine) domain of Sm and other nuclear proteins], anti-p105-PANA [proliferation-associated nuclear antigen; a marker of IGs (interchromatin granules)] and anti-DNA antibodies. In parallel, ultrastructural analysis, including cytochemical staining for RNA, phosphorylated proteins and DNA, was carried out. Splicing factors were distributed in a diffuse perichromosomal layer containing perichromatin granules and fibrils that co-localized with the decondensed peripheral DNA loops, but not with the main chromosome body. Interchromosomal domains with IGs and Cajal-like bodies were also detected. Conclusions. Dinoflagellates are rather dissimilar to other eukaryotes in their genomes, their mechanisms of gene expression and their chromosome ultrastructure. However, they share common splicing nuclear domains and snRNP biogenesis with that of other eukaryotes.
引用
收藏
页码:709 / 720
页数:12
相关论文
共 44 条
[1]   PREPARATION AND CHARACTERIZATION OF GONYAULAX SPHEROPLASTS [J].
ADAMICH, M ;
SWEENEY, BM .
PLANTA, 1976, 130 (01) :1-5
[2]   A NEW STAINING PROCEDURE FOR ELECTRON MICROSCOPICAL CYTOLOGY [J].
BERNHARD, W .
JOURNAL OF ULTRASTRUCTURE RESEARCH, 1969, 27 (3-4) :250-+
[3]   Opinion - Actin up in the nucleus [J].
Bettinger, BT ;
Gilbert, DM ;
Amberg, DC .
NATURE REVIEWS MOLECULAR CELL BIOLOGY, 2004, 5 (05) :410-415
[4]   A proteomic analysis of arginine-methylated protein complexes [J].
Boisvert, FM ;
Côté, J ;
Boulanger, MC ;
Richard, S .
MOLECULAR & CELLULAR PROTEOMICS, 2003, 2 (12) :1319-1330
[5]   The C-terminal RG dipeptide repeats of the spliceosomal Sm proteins D1 and D3 contain symmetrical dimethylarginines, which form a major B-cell epitope for anti-Sm autoantibodies [J].
Brahms, H ;
Raymackers, J ;
Union, A ;
de Keyser, F ;
Meheus, L ;
Lührmann, R .
JOURNAL OF BIOLOGICAL CHEMISTRY, 2000, 275 (22) :17122-17129
[6]   Symmetrical dimethylation of arginine residues in spliceosomal Sm protein B/B′ and the Sm-like protein LSm4, and their interaction with the SMN protein [J].
Brahms, H ;
Meheus, L ;
De Brabandere, V ;
Fischer, U ;
Lührmann, R .
RNA, 2001, 7 (11) :1531-1542
[7]  
Cerná A, 2004, EUR J HISTOCHEM, V48, P49
[8]   Cajal bodies: A long history of discovery [J].
Cioce, M ;
Lamond, AI .
ANNUAL REVIEW OF CELL AND DEVELOPMENTAL BIOLOGY, 2005, 21 :105-131
[9]  
COGLIATI R, 1973, CR ACAD SCI D NAT, V276, P3041
[10]   Chromosome territories, nuclear architecture and gene regulation in mammalian cells [J].
Cremer, T ;
Cremer, C .
NATURE REVIEWS GENETICS, 2001, 2 (04) :292-301