Small nucleolar RNA SNORD115
Encyclopedia
SNORD115 is a non-coding RNA
(ncRNA) molecule known as a small nucleoloar RNA
which usually functions in guiding the modification of other non-coding RNA
s. This type of modifiying RNA is usually located in the nucleolus
of the eukaryotic cell which is a major site of snRNA biogenesis. HBII-52 refers to the human gene, whereas RBII-52 is used for the rat gene and MBII-52 is used for naming the mouse gene.
HBII-52 belongs to the C/D box class of snoRNAs which contain the conserved sequence
motifs known as the C box (UGAUGA) and the D box (CUGA). Most of the members of the box C/D family function in directing site-specific 2'-O-methylation
of substrate RNAs.
In the human genome, HBII-52 is encoded in a tandemly repeated array with another C/D box snoRNA, HBII-85
, in the Prader-Willi syndrome
(PWS) region of chromosome 15. HBII-52 is found in 47 tandem near identical copies on human chromosome 15q11-13. This locus is maternally imprinted, meaning that only the paternal copy of the locus is transcribed. HBII-52 is exclusively expressed in the brain but is absent in PWS patients. HBII-52 lacks any significant complementarity with ribosomal RNA
s, but does have an 18 nucleotide
region of conserved complementarity to serotonin 2C receptor
mRNA. The serotonin 2C receptor is also expressed in the brain. It has been shown that this snoRNA is likely to bind to a silencing element of exon Vb increasing its inclusion and production of a functional spliceform of the serotonin 2C receptor.
A microdeletion in one family of the snoRNA HBII-52 has excluded it from playing a major role in the disease.
The chromosomal locus containing the SNORD115 gene cluster has been duplicated in many individuals with autistic traits
. A mouse model engineered to have a duplication of the SNORD115 cluster displays autistic-like behaviour.
There is evidence that a truncated form of MBII-52 (SNORD115 found in mouse) regulates the alternative splicing of the protein coding genes DPM2
, TAF1
, RALGPS1, PBRM1
, and CRHR1
.
Non-coding RNA
A non-coding RNA is a functional RNA molecule that is not translated into a protein. Less-frequently used synonyms are non-protein-coding RNA , non-messenger RNA and functional RNA . The term small RNA is often used for short bacterial ncRNAs...
(ncRNA) molecule known as a small nucleoloar RNA
SnoRNA
Small nucleolar RNAs are a class of small RNA molecules that primarily guide chemical modifications of other RNAs, mainly ribosomal RNAs, transfer RNAs and small nuclear RNAs...
which usually functions in guiding the modification of other non-coding RNA
Non-coding RNA
A non-coding RNA is a functional RNA molecule that is not translated into a protein. Less-frequently used synonyms are non-protein-coding RNA , non-messenger RNA and functional RNA . The term small RNA is often used for short bacterial ncRNAs...
s. This type of modifiying RNA is usually located in the nucleolus
Nucleolus
The nucleolus is a non-membrane bound structure composed of proteins and nucleic acids found within the nucleus. Ribosomal RNA is transcribed and assembled within the nucleolus...
of the eukaryotic cell which is a major site of snRNA biogenesis. HBII-52 refers to the human gene, whereas RBII-52 is used for the rat gene and MBII-52 is used for naming the mouse gene.
HBII-52 belongs to the C/D box class of snoRNAs which contain the conserved sequence
Conserved sequence
In biology, conserved sequences are similar or identical sequences that occur within nucleic acid sequences , protein sequences, protein structures or polymeric carbohydrates across species or within different molecules produced by the same organism...
motifs known as the C box (UGAUGA) and the D box (CUGA). Most of the members of the box C/D family function in directing site-specific 2'-O-methylation
Methylation
In the chemical sciences, methylation denotes the addition of a methyl group to a substrate or the substitution of an atom or group by a methyl group. Methylation is a form of alkylation with, to be specific, a methyl group, rather than a larger carbon chain, replacing a hydrogen atom...
of substrate RNAs.
In the human genome, HBII-52 is encoded in a tandemly repeated array with another C/D box snoRNA, HBII-85
Small nucleolar RNA SNORD116
SNORD116 is a non-coding RNA molecule which functions in the modification of other small nuclear RNAs . This type of modifiying RNA is usually located in the nucleolus of the eukaryotic cell which is a major site of snRNA biogenesis...
, in the Prader-Willi syndrome
Prader-Willi syndrome
Prader–Willi syndrome is a rare genetic disorder in which seven genes on chromosome 15 are deleted or unexpressed on the paternal chromosome...
(PWS) region of chromosome 15. HBII-52 is found in 47 tandem near identical copies on human chromosome 15q11-13. This locus is maternally imprinted, meaning that only the paternal copy of the locus is transcribed. HBII-52 is exclusively expressed in the brain but is absent in PWS patients. HBII-52 lacks any significant complementarity with ribosomal RNA
Ribosomal RNA
Ribosomal ribonucleic acid is the RNA component of the ribosome, the enzyme that is the site of protein synthesis in all living cells. Ribosomal RNA provides a mechanism for decoding mRNA into amino acids and interacts with tRNAs during translation by providing peptidyl transferase activity...
s, but does have an 18 nucleotide
Nucleotide
Nucleotides are molecules that, when joined together, make up the structural units of RNA and DNA. In addition, nucleotides participate in cellular signaling , and are incorporated into important cofactors of enzymatic reactions...
region of conserved complementarity to serotonin 2C receptor
5-HT2C receptor
The 5-HT2C receptor is a subtype of 5-HT receptor that binds the endogenous neurotransmitter serotonin . It is a G protein-coupled receptor that is coupled to Gq/G11 and mediates excitatory neurotransmission. HTR2C denotes the human gene encoding for the receptor, that in humans is located at the...
mRNA. The serotonin 2C receptor is also expressed in the brain. It has been shown that this snoRNA is likely to bind to a silencing element of exon Vb increasing its inclusion and production of a functional spliceform of the serotonin 2C receptor.
A microdeletion in one family of the snoRNA HBII-52 has excluded it from playing a major role in the disease.
The chromosomal locus containing the SNORD115 gene cluster has been duplicated in many individuals with autistic traits
Autism
Autism is a disorder of neural development characterized by impaired social interaction and communication, and by restricted and repetitive behavior. These signs all begin before a child is three years old. Autism affects information processing in the brain by altering how nerve cells and their...
. A mouse model engineered to have a duplication of the SNORD115 cluster displays autistic-like behaviour.
There is evidence that a truncated form of MBII-52 (SNORD115 found in mouse) regulates the alternative splicing of the protein coding genes DPM2
DPM2
Dolichol phosphate-mannose biosynthesis regulatory protein is a protein that in humans is encoded by the DPM2 gene.- Function :Dolichol-phosphate mannose serves as a donor of mannosyl residues on the lumenal side of the endoplasmic reticulum . Lack of Dol-P-Man results in defective surface...
, TAF1
TAF1
Transcription initiation factor TFIID subunit 1, also known as transcription initiation factor TFIID 250 kDa subunit or TBP-associated factor 250 kDa , is a protein that in humans is encoded by the TAF1 gene.-Function:...
, RALGPS1, PBRM1
PBRM1
Protein polybromo-1 also known as BRG1-associated factor 180 is a protein that in humans is encoded by the PBRM1 gene.- Structure and function :...
, and CRHR1
Corticotropin releasing hormone receptor 1
Corticotropin releasing hormone receptor 1 is a protein, also known as CRF1, with the latter now being the IUPHAR-recommended name...
.