SON
Identifiers
AliasesSON, BASS1, C21orf50, DBP-5, NREBP, SON3, SON DNA binding protein, TOKIMS, SON DNA and RNA binding protein
External IDsOMIM: 182465 MGI: 98353 HomoloGene: 10551 GeneCards: SON
Orthologs
SpeciesHumanMouse
Entrez

6651

20658

Ensembl

ENSG00000159140

ENSMUSG00000022961

UniProt

P18583

Q9QX47

RefSeq (mRNA)

NM_019973
NM_178880

RefSeq (protein)

NP_001278340
NP_001278341
NP_115571
NP_620305

NP_064357
NP_849211

Location (UCSC)Chr 21: 33.54 – 33.58 MbChr 16: 91.44 – 91.48 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

SON protein is a protein that in humans is encoded by the SON gene.[5][6]

SON is the name that has been given to a large Ser/Arg (SR)-related protein, which is a splicing co-factor that contributes to an efficient splicing within cell cycle progression.[7] It is also known as BASS1 (Bax antagonist selected in saccharomyces 1) or NRE-binding protein (Negative regulatory element-binding protein). The most common gene name of this splicing protein- which is only found in Humans (Homo sapiens)- is SON, but C21orf50, DBP5, KIAA1019 and NREBP can also be used as synonyms.[8]

The protein encoded by SON gene binds to a specific DNA sequence upstream of the upstream regulatory sequence of the core promoter and second enhancer of human hepatitis B virus (HBV). Through this binding, it represses HBV core promoter activity, transcription of HBV genes, and production of HBV virions. The protein shows sequence similarities with other DNA-binding structural proteins such as gallin, oncoproteins of the MYC family, and the oncoprotein MOS. It may also be involved in protecting cells from apoptosis and in pre-mRNA splicing.[6] Mutation in SON gene is associated with ZTTK syndrome.[9]

Structure

The sequence length of the SON protein consists in 2426 aminoacids and its sequence status is totally completed. Its molecular weight is 263,830 daltons (Da) and its domain contains 8 types of repeats which are distributed in 3 regions. This protein is found in the 21st chromosome and is mostly located in nuclear speckles. Its higher expression is seen in leukocyte and heart cells.[8][10]

Splicing process

Location of the gene that encodes the SON protein.

SON protein is essential for maintaining the subnuclear organization of the factors that are processed in the nucleus highlighting its direct role in pre-mRNA splicing.[11]

Splicing is the process through which pre-mRNA is transformed into mRNA. The pre-mRNA which has just been transcribed contains sequences called introns and exons. Introns are non-active nucleotide sequences that must be removed in order for the exons (active sequences) to be joined together forming mRNA. The controlled process of splicing takes place in the spliceosome, a complex that brings together pre-mRNA and a variety of binding proteins. These proteins together with the splicing factors (which are not found in the spliceosome) are in charge of recognizing the 5' ("donor") splice site, 3' ("acceptor") splice site, and branch point sequence within the intron. The SON protein is known to be one of these binding proteins.[11]

Although there is a lack of knowledge about its exact splicing control in the progression of the cell cycle and it has remained largely unexplored, it’s certain that this splicing-associated protein is necessary for the maintenance of the embryonic stem cells because it influences the splicing of pluripotency regulators.[7][12]

SON plays an important role in the mRNA processing. Nevertheless, this process is still a little uncertain and this is why in a future it will be interesting to understand how exactly this protein interacts with the spliceosomal complex, its exact molecular function in the context of splicing. Not only the SON protein interferes in the splicing but also makes complex mechanisms such as the RNA post-transcriptional to cooperate with the splicing-mRNA processing.[13]

Human embryonic stem cells are able to undergo the process of differentiation into specific and relevant cells. To maintain the pluripotency of the embryonic stem cells, transcription factors and epigenetic modifiers play an important role despite the fact that little is known about the regulation of pluripotency throughout the process of splicing. The factor SON is identified as essential for the maintenance of this pluripotency. It is confirmed that SON regulates the splicing process of transcripts (RNAm) that will encode the gens that are going to regulate the pluripotency of the embryonic human cells.[14]

Function

SON protein's intervention in the splicing process.

On the one hand, SON protein is required to maintain the genome stability in order to ensure an efficient RNA processing of affected genes. It also facilitates the interaction of SR proteins with RNA polymerase II and is required for processing of weak constitutive splice sites, having also strong implications in cancer and other human diseases.[7][10]

On the other side, a deficiency or knockdown of SON protein causes various and severe defects in mitotic division arrangement, chromosome alignment and microtubule dynamics when spindle pole separation takes place.[7]

But as we could read in the article called “SON protein regulates GATA-2 through transcriptional control of the microRNA 23a-27-24-a clúster”, SON protein has even more functions in the organism. It has been found that these proteins may regulate the hematopoietic cells differentiation. They have a specific job in hematopoietic process, which is based on activating other proteins called GATA. As these ones are finally activated, the cell differentiation starts normally.[15]

Clinical significance

A recent study suggested that SON may be a novel therapeutic molecular target for pancreatic cancer as the results of a recent study show that this protein is very important as far as proliferation, survival and tumorigenicity of cancer cells are concerned. Specifically, these results revealed that the serine-arginine-rich protein involved in the RNA splicing process, could suppress pancreatic cell tumorigenicity.[13]

The therapeutic implications of the SON gene within virus-host interactions, particularly in the context of viral infections, remain insufficiently defined. Although the SON gene is recognized for its engagement in diverse cellular processes like mRNA splicing, DNA repair, and cell cycle regulation, its precise involvement in the host's response to viral infections and its therapeutic applications remain ambiguous[16]). Ongoing research is dedicated to unraveling the intricate interactions between host genes, including SON, and HIV-1. This pursuit aims to enhance our comprehension of the dynamics between viruses and hosts, with the potential to unveil novel targets for therapeutic interventions.

RNA Processing and viral replication

SON plays a crucial role in mRNA splicing, a vital process for gene expression. Certain viruses depend on the host's cellular machinery, including the splicing apparatus, for their replication. Disrupting host factors involved in RNA processing could potentially impede viral replication. Aberrations in splicing processes may lead to abnormal protein production and contribute to disease.[17] Given SON's involvement in RNA processing, it emerges as a promising target for comprehending and treating conditions associated with splicing abnormalities.

Genetic and epigenetic approaches

In the event that SON is identified as a contributor to either promoting or inhibiting viral replication, there is potential for exploring genetic or epigenetic strategies. This could involve manipulating SON expression or activity to influence the viral life cycle.[18]

Immunomodulation

Host factors also play a role in shaping the immune response to viral infections. If SON is implicated in pathways related to the immune system, modulating its activity could have implications for enhancing the host's capacity to control viral infections.[19]

References

  1. 1 2 3 GRCh38: Ensembl release 89: ENSG00000159140 - Ensembl, May 2017
  2. 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000022961 - Ensembl, May 2017
  3. ↑ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ↑ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ↑ Cheng S, Lutfalla G, Uze G, Chumakov IM, Gardiner K (Aug 1993). "GART, SON, IFNAR, and CRF2-4 genes cluster on human chromosome 21 and mouse chromosome 16". Mammalian Genome. 4 (6): 338–342. doi:10.1007/BF00357094. PMID 8318737. S2CID 19770065.
  6. 1 2 "Entrez Gene: SON SON DNA binding protein".
  7. 1 2 3 4 Ahn EY, DeKelver RC, Lo MC, Nguyen TA, Matsuura S, Boyapati A, et al. (April 2011). "SON controls cell-cycle progression by coordinated regulation of RNA splicing". Molecular Cell. 42 (2): 185–198. doi:10.1016/j.molcel.2011.03.014. PMC 3137374. PMID 21504830.
  8. 1 2 "Protein SON". UniProt Consortium.
  9. ↑ "OMIM Entry- # 617140 - ZTTK SYNDROME; ZTTKS". omim.org. Retrieved 2017-10-27.
  10. 1 2 "Son peptide". MyBioSource.com.
  11. 1 2 Voet D, Voet JG (2011). Biochemistry. Hoboken, NJ: John Wiley Sons. ISBN 978-0-470-57095-1.
  12. ↑ Livyatan I, Meshorer E (October 2013). "SON sheds light on RNA splicing and pluripotency". Nature Cell Biology. 15 (10): 1139–1140. doi:10.1038/ncb2851. PMID 24084863. S2CID 12137904.
  13. 1 2 Furukawa T, Tanji E, Kuboki Y, Hatori T, Yamamoto M, Shimizu K, et al. (December 2012). "Targeting of MAPK-associated molecules identifies SON as a prime target to attenuate the proliferation and tumorigenicity of pancreatic cancer cells". Molecular Cancer. 11: 88. doi:10.1186/1476-4598-11-88. PMC 3576306. PMID 23227827.
  14. ↑ Lu X, Göke J, Sachs F, Jacques PÉ, Liang H, Feng B, et al. (October 2013). "SON connects the splicing-regulatory network with pluripotency in human embryonic stem cells". Nature Cell Biology. 15 (10): 1141–1152. doi:10.1038/ncb2839. PMC 4097007. PMID 24013217.
  15. ↑ Ahn EE, Higashi T, Yan M, Matsuura S, Hickey CJ, Lo MC, et al. (February 2013). "SON protein regulates GATA-2 through transcriptional control of the microRNA 23a~27a~24-2 cluster". The Journal of Biological Chemistry. 288 (8): 5381–5388. doi:10.1074/jbc.M112.447227. PMC 3581430. PMID 23322776.
  16. ↑ Lu X, Ng HH, Bubulya PA (Sep 2014). "The role of SON in splicing, development, and disease". Wiley Interdisciplinary Reviews. RNA. 5 (5): 637–646. doi:10.1002/wrna.1235. PMC 4138235. PMID 24789761.
  17. ↑ Ahn EY, DeKelver RC, Lo MC, Nguyen TA, Matsuura S, Boyapati A, et al. (April 2011). "SON controls cell-cycle progression by coordinated regulation of RNA splicing". Molecular Cell. 42 (2): 185–198. doi:10.1016/j.molcel.2011.03.014. PMC 3137374. PMID 21504830.
  18. ↑ Balakrishnan L, Milavetz B (November 2017). "Epigenetic Regulation of Viral Biological Processes". Viruses. 9 (11): 346. doi:10.3390/v9110346. PMC 5707553. PMID 29149060.
  19. ↑ Bernard-Raichon L, Cadwell K (September 2023). "Immunomodulation by Enteric Viruses". Annual Review of Virology. 10 (1): 477–502. doi:10.1146/annurev-virology-111821-112317. PMID 37380186. S2CID 259286197.

Further reading

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.