Small nucleolar RNA SNORD64

{{Infobox rfam

| Name = Small Nucleolar RNA SNORD64

| image = RF00570.jpg

| width =

| caption = Predicted secondary structure and sequence conservation of SNORD64

| Symbol = SNORD64

| AltSymbols = snoHBII-13

| Rfam = RF00570

| miRBase =

| miRBase_family =

| RNA_type = Gene; snRNA; snoRNA; C/D-box

| Tax_domain = Eukaryota

| GO = {{GO|0006396}} {{GO|0005730}}

| SO = {{SO|0000593}}

| CAS_number =

| EntrezGene =

| HGNCid =

| OMIM =

| PDB =

| RefSeq =

| Chromosome =

| Arm =

| Band =

| LocusSupplementaryData =

}}

In molecular biology, SNORD64 (also known as HBII-13) is a non-coding RNA (ncRNA) molecule which functions in the biogenesis (modification) of other small nuclear RNAs (snRNAs). This type of modifying RNA is located in the nucleolus of the eukaryotic cell which is a major site of snRNA biogenesis. It is known as a small nucleolar RNA (snoRNA) and also often referred to as a guide RNA.

SNORD64 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.{{cite journal | vauthors = Galardi S, Fatica A, Bachi A, Scaloni A, Presutti C, Bozzoni I | title = Purified box C/D snoRNPs are able to reproduce site-specific 2'-O-methylation of target RNA in vitro | journal = Molecular and Cellular Biology | volume = 22 | issue = 19 | pages = 6663–8 | date = October 2002 | pmid = 12215523 | pmc = 134041 | doi = 10.1128/MCB.22.19.6663-6668.2002 }}

snoRNA HBII-13 is expressed mainly in the tissues of brain, but is also in the lungs, the kidneys and muscle;{{cite journal | vauthors = Cavaillé J, Buiting K, Kiefmann M, Lalande M, Brannan CI, Horsthemke B, Bachellerie JP, Brosius J, Hüttenhofer A | title = Identification of brain-specific and imprinted small nucleolar RNA genes exhibiting an unusual genomic organization | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 97 | issue = 26 | pages = 14311–6 | date = December 2000 | pmid = 11106375 | pmc = 18915 | doi = 10.1073/pnas.250426397 | doi-access = free }} however HBII-13 has no identified target RNA.{{cite journal | vauthors = Lestrade L, Weber MJ | title = snoRNA-LBME-db, a comprehensive database of human H/ACA and C/D box snoRNAs | journal = Nucleic Acids Research | volume = 34 | issue = Database issue | pages = D158-62 | date = January 2006 | pmid = 16381836 | pmc = 1347365 | doi = 10.1093/nar/gkj002 | citeseerx = 10.1.1.105.7552 }}

The HBII-13 gene is located in a 460 kb intron of the large paternally-expressed transcription unit (SNURF-SNRNP-UBE3A AS) along with several other snoRNAs HBII-436, HBII-437, HBII-438A/B and the clusters of HBII-85, HBII-52.{{cite journal | vauthors = Runte M, Hüttenhofer A, Gross S, Kiefmann M, Horsthemke B, Buiting K | title = The IC-SNURF-SNRPN transcript serves as a host for multiple small nucleolar RNA species and as an antisense RNA for UBE3A | journal = Human Molecular Genetics | volume = 10 | issue = 23 | pages = 2687–700 | date = November 2001 | pmid = 11726556 | doi = 10.1093/hmg/10.23.2687 | doi-access = }} This host gene is an antisense transcript to maternally expressed UBE3A gene.