Transmembrane protein 229b is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

that in humans is encoded by the TMEM229b

gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ...

Nomenclature

The TMEM229B gene is also known as C14orf83, FLJ33387, Q8NBD8, Hs.509707, Hs.712258, IPR010540, and CN083_HUMAN.

Gene

The TMEM229B gene is located on the

sense strand In genetics, a sense strand, or coding strand, is the segment within double-stranded DNA that carries the translatable code in the 5′ to 3′ direction, and which is complementary to the antisense strand of DNA, or template strand, which does ...

(-) of chromosome 14 at location 14q24.1 and spans the chromosomal locus 67,936,983—67,982,021. Covering a total of 45,038

base pairs A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

(bp) along the chromosome, the TMEM229B gene has a total of 3 exons in its primary unspliced transcript

mRNA In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is ...

of 4,068 bp. There are a total of 7 transcript variants for TMEM229B ranging in mRNA size from 519 bp to 5008 bp. The TMEM229B gene is flanked by phosphatidylinositol glycan anchor class H ( PIGH), a protein associated with the endoplasmic reticulum specifically GPI-anchor biosynthesis, and PLEK2 on its left. See Figure 1.0. The gene is highly conserved in vertebrates, including portions of the approximately 3,000 base pairs of 3'UTR.

Tissue distribution

Expressed sequence tag In genetics, an expressed sequence tag (EST) is a short sub-sequence of a cDNA sequence. ESTs may be used to identify gene transcripts, and were instrumental in gene discovery and in gene-sequence determination. The identification of ESTs has pro ...

mapping of TMEM229B gene expression indicates that it is ubiquitously expressed throughout the body. TMEM229B is more heavily expressed in the

parathyroid Parathyroid glands are small endocrine glands in the neck of humans and other tetrapods. Humans usually have four parathyroid glands, located on the back of the thyroid gland in variable locations. The parathyroid gland produces and secretes pa ...

, skin, and

thyroid The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans, it is a butterfly-shaped gland located in the neck below the Adam's apple. It consists of two connected lobes. The lower two thirds of the lobes are connected by ...

tissues, and moderately expressed in bone marrow, trachea, spleen, eye, brain, pancreas, mammary gland, intestine, liver, thymus, lymph node, ovarian, muscle, lung, blood, and kidney tissues.

Protein

The translated TMEM229B protein is a total of 167 amino acids long, with a predicted

molecular weight A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, the term may or may not include ions that satisfy this criterion. In quantum physics, organic chemi ...

of 19,531 daltons. The TMEM229B protein contains a domain of unknown function, part of the domain family DUF1113, spanning from

amino acid Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although over 500 amino acids exist in nature, by far the most important are the 22 α-amino acids incorporated into proteins. Only these 22 a ...

s 87 to 135. Based on predicted structure TMEM229b is highly resemblant of a

connexin Connexins (Cx)TC# 1.A.24, or gap junction proteins, are structurally related transmembrane proteins that assemble to form vertebrate gap junctions. An entirely different family of proteins, the innexins, forms gap junctions in invertebrates. Eac ...

subunit. A highly conserved phosphorylation site exists at the Threonine-139 position. See multiple sequence alignment below. File:TMEM229_b.jpg, Annotated diagram of the TMEM229b gene (with its 3 exons), mature mRNA and protein domains. Functional peptide is predicted to take the form of a connexin 4-pass transmembrane subunit (seen below).

Clinical relevance

Expression of the TMEM229B gene increases in several disease states including amelanotic skin melanoma, B-cell neoplasm,

breast carcinoma Breast cancer is a cancer that develops from breast tissue. Signs of breast cancer may include a lump in the breast, a change in breast shape, dimpling of the skin, milk rejection, fluid coming from the nipple, a newly inverted nipple, or ...

Burkitt's lymphoma Burkitt's lymphoma is a cancer of the lymphatic system, particularly B lymphocytes found in the germinal center. It is named after Denis Parsons Burkitt, the Irish surgeon who first described the disease in 1958 while working in equatorial Africa ...

, colorectal adenocarcinoma, carcinoma, cutaneous T cell lymphoma, esophageal carcinoma,

gastric carcinoma Stomach cancer, also known as gastric cancer, is a malignant tumor of the stomach. It is a cancer that develops in the lining of the stomach. Most cases of stomach cancers are gastric carcinomas, which can be divided into a number of subtypes ...

glioblastoma Glioblastoma, previously known as glioblastoma multiforme (GBM), is the most aggressive and most common type of cancer that originates in the brain, and has a very poor prognosis for survival. Initial signs and symptoms of glioblastoma are nons ...

, liver carcinoma,

lymphoma Lymphoma is a group of blood and lymph tumors that develop from lymphocytes (a type of white blood cell). The name typically refers to just the cancerous versions rather than all such tumours. Signs and symptoms may include enlarged lymph node ...

melanoma Melanoma is the most dangerous type of skin cancer; it develops from the melanin-producing cells known as melanocytes. It typically occurs in the skin, but may rarely occur in the mouth, intestines, or eye (uveal melanoma). In very rare case ...

small cell lung carcinoma Small-cell carcinoma, also known as oat cell carcinoma, is a type of highly malignant cancer that most commonly arises within the lung, although it can occasionally arise in other body sites, such as the cervix, prostate, and gastrointestinal tr ...

, T-cell acute lymphoblastic leukemia,

thyroid carcinoma Thyroid neoplasm is a neoplasm or tumor of the thyroid. It can be a benign tumor such as thyroid adenoma, or it can be a malignant neoplasm (thyroid cancer), such as papillary, follicular, medullary or anaplastic thyroid cancer.Hu MI, Vassilo ...

and

Wilms' tumor Wilms' tumor or Wilms tumor, also known as nephroblastoma, is a cancer of the kidneys that typically occurs in children (rarely in adults), and occurs most commonly as a renal tumor in child patients. It is named after Max Wilms, the German sur ...

as found in several

microarray A microarray is a multiplex (assay), multiplex lab-on-a-chip. Its purpose is to simultaneously detect the expression of thousands of biological interactions. It is a two-dimensional array on a Substrate (materials science), solid substrate—usu ...

experiments. Over-expression of the TMEM229B gene has not been linked as a causal factor in any of these disease states.

References

{{DEFAULTSORT:Tmem229b Proteins Genes on human chromosome 14