12 S small nuclear ribonucleoprotein-associated acidic and pyrimidine-specific endoribonuclease from calf thymus and L5178y cells

Bachmann, Michael; Messer, Rudolf; Trautmann, F; Müller, Wernér E.G.

doi:10.1016/0167-4781(84)90082-4

Cited by 10 publications

(11 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…XendoU is a novel endoribonuclease in that it requires Mn 2ϩ ions and produces 2Ј-3Ј-cyclic phosphate termini. Such ends have been previously associated solely with metal-independent (2,30) or Mg 2ϩ -dependent endoribonucleases (31)(32)(33). On the contrary, Mn 2ϩ -requiring endonucleases usually produce 5Ј-P and 3Ј-OH ends (34,35).…”

Section: Discussionmentioning

confidence: 99%

Purification, Cloning, and Characterization of XendoU, a Novel Endoribonuclease Involved in Processing of Intron-encoded Small Nucleolar RNAs in Xenopus laevis

Laneve

Altieri

Fiori

et al. 2003

Journal of Biological Chemistry

126

View full text Add to dashboard Cite

Here we report the purification, from Xenopus laevis oocyte nuclear extracts, of a new endoribonuclease, XendoU, that is involved in the processing of the intronencoded box C/D U16 small nucleolar RNA (snoRNA) from its host pre-mRNA. Such an activity has never been reported before and has several uncommon features that make it quite a novel enzyme: it is poly(U)-specific, it requires Mn 2؉ ions, and it produces molecules with 2-3-cyclic phosphate termini. Even if XendoU cleaves U-stretches, it displays some preferential cleavage on snoRNA precursor molecules. XendoU also participates in the biosynthesis of another intron-encoded snoRNA, U86, which is contained in the NOP56 gene of Xenopus laevis. A common feature of these snoRNAs is that their production is alternative to that of the mRNA, suggesting an important regulatory role for all the factors involved in the processing reaction.Endoribonucleases play essential roles in RNA metabolism participating both in degradative pathways, such as mRNA decay, and in maturative pathways, to generate functional RNA molecules (1, 2). Despite the plethora of functions played by processing enzymes in RNA metabolism, in eukaryotes only a few endoribonucleases have been isolated to date. Most of these activities are involved in the biosynthesis of translation components. In particular, RNase P and RNase mitochondrial RNA processing are ribonucleoprotein enzymes, functioning as site-specific endoribonucleases (3, 4). Other well characterized endonucleolytic activities, such as the 3Ј-tRNase, the tRNA splicing endonuclease, and members of the RNase III-like family are protein-only enzymes (5-7). Although the majority of these activities participate in the biosynthesis of a specific class of RNA molecules, RNase III was shown to be required for a large number of different maturative pathways. Saccharomyces cerevisiae RNase III (Rnt1p) was shown to be involved in pre-rRNA, small nuclear RNA (snRNA), 1 and small nucleolar RNA (snoRNA) processing (8 -12). Recently, Rnt1p was also shown to participate in processing the intron-encoded snoRNAs U18 and snR38 from their host pre-mRNA (13). Furthermore, a new member of the metazoan RNase III family has been identified to be involved in the RNA interference process (14).Another process in which the participation of endoribonucleases was expected to play an important role is the biosynthesis of snoRNAs. These RNAs are part of a complex class of molecules that are localized in the nucleolus where they participate, as small ribonucleoprotein particles (snoRNPs), in different rRNA maturative events such as processing and nucleotide modifications (15,16). Most snoRNAs in vertebrates are encoded in introns of protein-coding genes and are released from the host primary transcript either by debranching and exotrimming of the spliced lariat (splicing-dependent pathway) or by endonucleolytic cleavage of the pre-mRNA (splicing-independent pathway) (15, 16). There are only a few cases of intronencoded snoRNAs in vertebrates, which are released throug...

show abstract

Section: Discussionmentioning

confidence: 99%

Purification, Cloning, and Characterization of XendoU, a Novel Endoribonuclease Involved in Processing of Intron-encoded Small Nucleolar RNAs in Xenopus laevis

Laneve

Altieri

Fiori

et al. 2003

Journal of Biological Chemistry

126

View full text Add to dashboard Cite

show abstract

“…The cells were washed with buffer A (10 mM Tris HCl, pH 7.4/150 mM NaCl) and resuspended in 60 ml ofbuffer A and homogenized for 5 min by an Ultra Turrax (Janke-Kunkel, Staufen, F.R.G.). Subsequently, the homogenate was sonicated and centrifuged (15). The supernatant (crude extract) was brought to 45% saturation with (NH4)2SO4.…”

mentioning

confidence: 99%

“…The formed immunocomplexes were isolated by affinity chromatography on protein A-Sepharose (23). RNA was isolated from these complexes and fractionated on onedimensional polyacrylamide gels as described (15).…”

mentioning

confidence: 99%

Association of La and Ro antigens with intracellular structures in HEp-2 carcinoma cells.

Bachmann¹,

Mayet²,

Schröder³

et al. 1986

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Monoclonal antibodies were raised against homogeneous Ro and La antigens, two proteins associated with Ro and La ribonucleoproteins (RNPs). The specificity of the monoclonal antibodies was proven by immunoblot analysis and by immunoprecipitation. The anti-Ro antibody reacted with a Mr 95,000 protein in a mouse lymphoma cell extract and with a Mr 60,000 polypeptide in extracts from human spleen. The anti-La antibody recognized a Mr 50,000 polypeptide in the mouse L5178y cell extract. (3,4). RNA analysis revealed that Ro small cytoplasmic RNPs (scRNPs) carry the La as well as the Ro determinants and, consequently, were a subclass of La RNPs (5). Based on immunoprecipitation studies, the molecular weight of the Ro antigen(s) was determined to be 94,000 (90,000) (6), while analysis by immunoblotting revealed a Mr of 57,000 (7). Comparative experiments using the techniques of counterimmunoelectrophoresis and immunoblotting led to the assumption that the Ro antigenic determinant is labile when exposed to NaDodSO4 (8 (Junction City, OR).Preparation of the Anti-Ro and Anti-La mAbs. Homogeneous Ro and La antigens were prepared from L5178y mouse lymphoma cells (38). Briefly, crude cell extracts were enriched for Ro and La antigens by ammonium sulfate fractionation (45-80% saturation), ribonuclease A treatment, and Sephadex G-150 gel filtration. This extract was further purified by immunoaffinity column chromatography with monospecific antibodies against the Ro and La antigens according to the procedure described below for the application of mAbs. The antisera were obtained from patients with autoimmune disorders. The homogeneity of the antigen preparations was proven by NaDodSO4/gel electrophoresis, and their specificities, by immunoblotting (12) with standardized reference antisera (anti-Ro and anti-La; Centers for Disease Control, Atlanta). General procedures for preparation of mAbs (12,13)

show abstract

“…The purification procedure has been described previously [9,10]. The precipitate was collected by centrifugation, dissolved in 5 mlO.9%.…”

Section: Biotinylation Of Ro-mabmentioning

confidence: 99%

A monoclonal Ro‐antibody and the serum of a Ro‐positive patient with subacute cutaneous lupus erythematosus (SCLE) react with basal layers of human epidermis

Mayet¹,

Bachmann²,

Pfeifer³

et al. 1988

Eur J Clin Investigation

View full text Add to dashboard Cite

Abstract. Skin lesions, especially at areas exposed to sunlight, prove to be a major form of manifestation of diseases related to Ro-antibodies and neonatal-, 'ANA-negative-', and cutaneous types of lupus erythematosus. A monoclonal Ro-antibody established by our group reacts with a 60 kD polypeptide in extracts from human spleen, whereas in extracts from human epidermis the monoclonal Ro-antibody and a purified Ro-antibody from a monospecific serum of a patient with subacute cutaneous lupus erythematosus reacted with a 60 kD and a 48 kD protein. Performing immunofluorescence microscopy on HEp2-cells both antibodies showed a nuclear speckled staining pattern and a reaction with cytokeratin filaments. On skin biopsies obtained from the patient, predominantly the basal layers of the proliferative stratum germinativum demonstrated a high rate of immunofluorescence; antigen-expression seems to depend on sunlight exposure. From these data we assume that, especially in subacute cutaneous lupus erythematosus, cross-reaction of the Ro-antibody with one of the lower molecular keratins happens in that area of human epidermis which histologically shows cellular destruction.

show abstract

12 S small nuclear ribonucleoprotein-associated acidic and pyrimidine-specific endoribonuclease from calf thymus and L5178y cells

Cited by 10 publications

References 33 publications

Purification, Cloning, and Characterization of XendoU, a Novel Endoribonuclease Involved in Processing of Intron-encoded Small Nucleolar RNAs in Xenopus laevis

Purification, Cloning, and Characterization of XendoU, a Novel Endoribonuclease Involved in Processing of Intron-encoded Small Nucleolar RNAs in Xenopus laevis

Association of La and Ro antigens with intracellular structures in HEp-2 carcinoma cells.

A monoclonal Ro‐antibody and the serum of a Ro‐positive patient with subacute cutaneous lupus erythematosus (SCLE) react with basal layers of human epidermis

Contact Info

Product

Resources

About