Proline-rich protein 16 (PRR16) is a protein coding gene in Homo sapiens. [1] The protein is known by the alias Largen.
PRR16 is located on the long arm of chromosome 5. It is found at position 5q23.1. It has five known transcripts. [2]
Cytogenic band: 5q23.1
The image above shows chromosome five and the various gene locations on it. PRR16 can be seen at the thin red band that has been placed at q23.
PRR16 spans 330,365 bases and encodes for a mRNA that is 1,707 nucleotides. The resulting protein is 304 amino acids long. [1]
PRR16 has five known splice variants, each with a different processed transcript. 
[4]
There are three known isoforms of PRR16. Isoform 2 contains an additional exon in the 5' region, and it thus differs in the 5' UTR and initiates translation at an alternate start codon, compared to variant 1. Isoform 3 has two variants. The first contains an alternate 5' terminal exon, and it thus differs in the 5' UTR and initiates translation at a downstream in-frame start codon, compared to variant 1. The second contains alternate 5' exon structure, and it thus differs in the 5' UTR and initiates translation at a downstream in-frame start codon, compared to variant 1. All three isoforms are shorter at the N-terminus, compared to isoform 1. [1]
The PRR16 protein is 304 amino acids in length. It has a molecular weight of 32.8 kDa and an isoelectric point of 8.09. [5] [6] The protein does not interact with the membrane.
The only predictable feature of the PRR16 protein is an α-helix near the N-terminus, spanning about thirty amino acids. The remainder of the protein has a disordered structure. [7]
This structure was predicted by analyzing the amino acid sequence using I-TASSER. The final result can be seen below. [8]
The k-NN tool suggests the location of PRR16 in the nucleus of the cell with 52.2% certainty. The cytoplasm was predicted with 30.4% certainty, The following locations were predicted with 4.3% certainty: cytoskeleton, plasma membrane, mitochondria, and peroxisome. [14]
The PRR16 gene is expressed at very low levels throughout the body. It is expressed in the skeletal muscle, heart, lung, skin, portions of the brain, and bone marrow. [15]
| Protein | Function [16] | Tool |
|---|---|---|
| Abelson-interactor 2 (ABI2) | Regulation of cell growth and actin filament reorganization | Biogrid, [17] IntAct, [18] Mentha [19] |
| Amyloid precursor protein (APP) | Caspase activation and degeneration of both neuronal cell bodies | Biogrid, InnateDB, [20] Mentha |
| Death-associated protein kinase 1 (DAPK1) | Positive mediator of programmed cell death | Biogrid, IntAct |
| Neural precursor cell expressed developmentally downregulated protein 4-like (NEDD4L) | E3 ubiquitin-protein ligase | Biogrid, InnateDB, Mentha |
| Neural precursor cell expressed developmentally downregulated protein 4 (NEDD4) | E3 ubiquitin-protein ligase | Biogrid, InnateDB |
| Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) | Involved in gastrointestinal immunity | Biogrid |
| Protein phosphatase 1 catalytic subunit alpha (PPP1CA) | Cell division, regulation of glycogen metabolism, muscle contractility, and protein synthesis | Biogrid, InnateDB, IntAct, Mentha |
| Protein phosphatase 1 catalytic subunit gamma (PPP1CC) | Cell division, regulation of glycogen metabolism, muscle contractility, and protein synthesis | Biogrid, InnateDB, Mentha |
| SMAD ubiquitin regulatory factor 1 (SMURF1) | E3 ubiquitin-protein ligase | Biogrid, Mentha |
There are two isoforms of Inhibitory synaptic factor 1 that are known paralogs of PRR16.
PRR16 is found in all classes of vertebrates, including mammals, birds, fish, reptiles and amphibians. The most distant ortholog of PRR16 is in Branchiostoma belcheri and Branchiostoma floridae, which diverged an estimated 684 million years ago. [22] The gene has not been found in any plants, fungi or single celled organisms. The table below compares the known orthologs. [23]
| Organism | Common Name | Class | Accession Number | Sequence Identity | Sequence Similarity |
|---|---|---|---|---|---|
| Homo sapiens | Human | Mammalia | NP_001287712.1 | 100% | 100% |
| Pan paniscus | Bonobo | Mammalia | XP_003826752.1 | 99% | 100% |
| Mus musculus | House mouse | Mammalia | NP_001074693.1 | 93% | 95% |
| Ochotona princeps | American pika | Mammalia | XP_004586413.1 | 91% | 94% |
| Vombatus ursinus | Common wombat | Mammalia | XP_027730777.1 | 87% | 81% |
| Podarcis muralis | Common wall lizard | Reptilia | XP_028604016.1 | 88% | 91% |
| Alligator sinensis | Chinese alligator | Reptilia | XP_006033732.1 | 86% | 89% |
| Chrysemys picta bellii | Painted turtle | Reptilia | XP_005305197.1 | 88% | 91% |
| Pogona vitticeps | Central bearded dragon | Reptilia | XP_020659290.1 | 84% | 86% |
| Pseudonaja textilis | Eastern brown snake | Reptilia | XP_026576168.1 | 81% | 84% |
| Gallus gallus | Chicken | Aves | XP_001232593.3 | 81% | 85% |
| Columba livia | Rock pigeon | Aves | XP_005506281.1 | 85% | 89% |
| Haliaeetus leucocephalus | Bald eagle | Aves | XP_010560635.1 | 82% | 86% |
| Empidonax traillii | Willow flycatcher | Aves | XP_027735123.1 | 82% | 86% |
| Nanorana parkeri | High Himalaya frog | Amphibia | XP_018426570.1 | 71% | 79% |
| Xenopus tropicalis | Western clawed frog | Amphibia | XP_017946181.1 | 72% | 79% |
| Lepisosteus oculatus | Spotted gar fish | Actinopterygii | XP_006626913.1 | 65% | 77% |
| Callorhinchus milii | Australian ghostshark | Chondrichthyes | XP_007897515.1 | 64% | 75% |
| Branchiostoma belcheri | Lancelet | Amphioxiformes | XP_019614579.1 | 47% | 78% |
| Branchiostoma floridae | Lancelet | Amphioxiformes | XP_002601582.1 | 47% | 78% |
Protein YIF1A is a protein that in humans is encoded by the YIF1A gene.
Interferon-inducible GTPase 5 also known as immunity-related GTPase cinema 1 (IRGC1) is an enzyme that in humans is coded by the IRGC gene. It is predicted to behave like other proteins in the p47-GTPase-like and IRG families. It is most expressed in the testis.
Proline-rich 12 (PRR12) is a protein of unknown function encoded by the gene PRR12.
Transmembrane protein 241 is a ubiquitous sugar transporter protein which in humans is encoded by the TMEM241 gene.
PRR29 is a protein located on human chromosome 17 that in humans is encoded by the PRR29 gene.
Chromosome 16 open reading frame 46 is a protein of yet to be determined function in Homo sapiens. It is encoded by the C16orf46 gene with NCBI accession number of NM_001100873. It is a protein-coding gene with an overlapping locus.
TMEM44 is a protein that in humans is encoded by the TMEM44 gene. DKFZp686O18124 is a synonym of TMEM44.
C2orf81 is a human gene encoding protein c2orf81, which is predicted to have nuclear localization.
Testis-expressed protein 9 is a protein that in humans is encoded the TEX9 gene. TEX9 that encodes a 391-long amino acid protein containing two coiled-coil regions. The gene is conserved in many species and encodes orthologous proteins in eukarya, archaea, and one species of bacteria. The function of TEX9 is not yet fully understood, but it is suggested to have ATP-binding capabilities.
Chromosome 4 open reading frame 51 (C4orf51) is a protein which in humans is encoded by the C4orf51 gene.
Cilia- and flagella-associated protein 299 (CFAP299), is a protein that in humans is encoded by the CFAP299 gene. CFAP299 is predicted to play a role in spermatogenesis and cell apoptosis.
Transmembrane protein 155 is a protein that in humans is encoded by the TMEM155 gene. It is located on human chromosome 4, spanning 6,497 bases. It is also referred to as FLJ30834 and LOC132332. This protein is known to be expressed mainly in the brain, placenta, and lymph nodes and is conserved throughout most placental mammals. The function and structure of this protein is still not well understood, but its level of expression has been studied pertaining to various pathologies.
C1orf122 is a gene in the human genome that encodes the cytosolic protein ALAESM.. ALAESM is present in all tissue cells and highly up-regulated in the brain, spinal cord, adrenal gland and kidney. This gene can be expressed up to 2.5 times the average gene in its highly expressed tissues. Although the function of C1orf122 is unknown, it is predicted to be used for mitochondria localization.
Uncharacterized protein C17orf78 is a protein encoded by the C17orf78 gene in humans. The name denotes the location of the parent gene, being at the 78th open reading frame, on the 17th human chromosome. The protein is highly expressed in the small intestine, especially the duodenum. The function of C17orf78 is not well defined.
Leucine rich single-pass membrane protein 2 is a single-pass membrane protein rich in leucine, that in humans is encoded by the LSMEM2 gene. The LSMEM2 protein is conserved in mammals, birds, and reptiles. In humans, LSMEM2 is found to be highly expressed in the heart, skeletal muscle and tongue.
TMEM275 is a protein that in humans is encoded by the TMEM275 gene. TMEM275 has two, highly-conserved, helical trans-membrane regions. It is predicted to reside within the plasma membrane or the endoplasmic reticulum's membrane.
FAM120AOS, or family with sequence similarity 120A opposite strand, codes for uncharacterized protein FAM120AOS, which currently has no known function. The gene ontology describes the gene to be protein binding. Overall, it appears that the thyroid and the placenta are the two tissues with the highest expression levels of FAM120AOS across a majority of datasets.
Family with Sequence Similarity 166, member C (FAM166C), is a protein encoded by the FAM166C gene. The protein FAM166C is localized in the nucleus. It has a calculated molecular weight of 23.29 kDa. It also contains DUF2475, a protein of unknown function from amino acid 19-85. The FAM166C protein is nominally expressed in the testis, stomach, and thyroid.
Proline-rich protein 29, encoded by the PRR29 gene in humans, is a protein which is located in the human genome at 17q23. Its function is not fully understood. Its name is derived from the chain of 5 proline amino acids located toward the end of the protein. The primary domain within the sequence of this protein is known as DUF4587. It is reported to have high levels of expression in tissues pertaining to the circulatory system and the immune system. It is hypothesized that PRR29 is a nuclear protein that facilitates communication between the nucleus and the mitochondria.
Chromosome 5 open reading frame 22 (c5orf22) is a protein-coding gene of poorly characterized function in Homo sapiens. The primary alias is unknown protein family 0489 (UPF0489).
Attribution: Contains public domain text from https://www.ncbi.nlm.nih.gov/gene/51334
