Dyskeratosis Congenita
Dongyou Liu in Handbook of Tumor Syndromes, 2020
TCAB1 is another AR DC gene. TCAB1 is a telomerase holoenzyme protein that facilitates trafficking of telomerase to Cajal bodies, the nuclear sites of nucleoprotein complex modification and assembly. Compound heterozygous mutations in TCAB1 cause alteration of the nuclear localization of telomerase, so it cannot elongate telomeres, thereby resulting in short telomeres. A heterozygous mutation was found on the conserved telomere maintenance component 1 gene (CTC1). This implication is also associated with a pleiotropic syndrome, Coats plus [18,22].
Cell Biology
C.S. Sureka, C. Armpilia in Radiation Biology for Medical Physicists, 2017
The subnuclear organelles are specialized regions or nonmembranous small bodies having proteins and RNA. It includes nucleoli or nucleolus, Cajal bodies, and speckles. The nucleolus is the major site for the synthesis of ribosomal subunits and assembles ribosomes. Cajal bodies are found in the nucleus of proliferative cells like embryonic cells and tumor cells or metabolically active cells. Speckles are enriched in pre-messenger RNA splicing factors and are located in the interchromatin regions of the nucleoplasm.
Introduction to Molecular Biology
Martin G. Pomper, Juri G. Gelovani, Benjamin Tsui, Kathleen Gabrielson, Richard Wahl, S. Sam Gambhir, Jeff Bulte, Raymond Gibson, William C. Eckelman in Molecular Imaging in Oncology, 2008
Small nucleolar RNAs (snoRNA) are a large group of snRNAs located in the nucleus and the cajal bodies of eukaryotic cells. These are small RNA molecules that play an essential role in RNA biogenesis, particularly in ribosome formation by splicing the 45S rRNA precursor into 28S, 18S, and 5S molecules. snoRNAs also guide chemical modifications of nucleotides in rRNAs and other RNA genes.
Therapeutic interventions for spinal muscular atrophy: preclinical and early clinical development opportunities
Published in Expert Opinion on Investigational Drugs, 2021
Laurent Servais, Giovanni Baranello, Mariacristina Scoto, Aurore Daron, Maryam Oskoui
SMN is ubiquitously expressed in all cells and is highly conserved across species. SMN is concentrated in the Cajal bodies, a nuclear structure essential in spliceosomal snRNP biogenesis, and is also present in the cytoplasm. The SMN protein is critical for motoneuron development and maintenance, with highest levels of expression during fetal development and early postnatal period [4]. A lower level of expression of SMN is needed throughout life [4]. Its complete absence is embryonically lethal across all species. Spinal and bulbar motoneurons are especially sensitive to the lack of SMN protein, leading to the characteristic motor features SMA. SMN functions in spliceosome assembly and ribonucleoprotein biogenesis in all cells [2] and is potentially involved in autophagy, endocytosis, mRNA trafficking and local translation, cytoskeletal dynamics, mitochondria and bioenergetic pathways, and ubiquitin-proteasome system [5], leading to additional systemic effects mainly observed in humans in the most severe cases [6,7]. There is accumulating evidence from animal models of SMA for the involvement of muscle [8], NMJs [9], liver [10], heart [11], and vascular endothelium [12] in the pathology of SMA, but clear evidence of clinical involvement of these organs in humans is limited to the most severe SMA cases.
Unfolding the Role of Splicing Factors and RNA Debranching in AID Mediated Antibody Diversification
Published in International Reviews of Immunology, 2021
Ankit Jaiswal, Amit Kumar Singh, Anubhav Tamrakar, Prashant Kodgire
CTNNBL1 being a part of CDC5L and Prp19 complex [89] that is localized in the Cajal body (CB), so is it possible that AID and CTNNBL1 were also present in the CB. Thus, it is worth exploring that if AID and CTNNBL1 are localized in the CB, and if they are localized, do they interact with the CB associated proteins. CB is the structure present in the nucleus that is the home to snRNPs and splicing factors. Survival of Motor Neuron (SMN) protein and coilin protein are the most abundant proteins found in the CB. Subsequent experiments confirmed that CTNNBL1 and AID are localized with CB associated proteins SMN in live HeLa cells, as well as fixed cells. Additionally, CTNNBL1 and AID were found to interact with CB associated proteins SMN as well as coilin as demonstrated by CoIP experiments. Interestingly, AID 1-81 amino acids are indispensable for its localization to the CB [70]. Moreover, AID localization to the CB is independent of its interaction with CTNNBL1. Finally, it can be concluded that AID and CTNNBL1 are localized at the CB as well as interact with CB associated proteins [70].
Developments in lncRNA drug discovery: where are we heading?
Published in Expert Opinion on Drug Discovery, 2018
Ilya Blokhin, Olga Khorkova, Jane Hsiao, Claes Wahlestedt
Substantial progress in the noncoding RNA field was made in the 1990s, when microRNAs (miRs) and small interfering RNAs (siRNAs) were described [7–9]. Both miR and siRNA are short (~20 nucleotides) noncoding RNAs that can be incorporated into the RNA-induced silencing complex (RISC) and contribute to post-transcriptional inhibition of protein-coding RNA in the cytoplasm. MiRs are involved in regulating ~60% of known mRNA [10] and thus play a role in the majority of cellular and physiological processes. SiRNAs were discovered in 1998 and since then have become one of the most common tools in molecular biology, with translational efforts in progress (see the following text). Other functionally important classes of noncoding RNA discovered in the 1990s and 2000s include PIWI-interacting RNA (piRNAs) that silence retrotransposons, small Cajal body-specific RNAs (scaRNAs) responsible for posttranscriptional modifications of snRNAs, and transcription initiation RNAs (tiRNAs).
Related Knowledge Centers
- Protein
- Rna
- Blastomere
- Neoplasm
- Cell Nucleus
- Organelle
- Nucleolus
- Nuclear Bodies
- Cell
- Neuron