TIA1 or Tia1 cytotoxic granule-associated rna binding protein is a 3'UTR

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 ...

binding protein that can bind the 5'TOP sequence of 5'TOP mRNAs. It is associated with programmed cell death (

apoptosis Apoptosis (from ) is a form of programmed cell death that occurs in multicellular organisms and in some eukaryotic, single-celled microorganisms such as yeast. Biochemistry, Biochemical events lead to characteristic cell changes (Morphology (biol ...

) and regulates

alternative splicing Alternative splicing, alternative RNA splicing, or differential splicing, is an alternative RNA splicing, splicing process during gene expression that allows a single gene to produce different splice variants. For example, some exons of a gene ma ...

of the gene encoding the

Fas receptor The Fas receptor, also known as Fas, FasR, apoptosis antigen 1 (APO-1 or APT), cluster of differentiation 95 (CD95) or tumor necrosis factor receptor superfamily member 6 (TNFRSF6), is a protein that in humans is encoded by the ''FAS'' gene. Fas ...

, an apoptosis-promoting protein. Under stress conditions, TIA1 localizes to cellular RNA-protein conglomerations called stress granules. It is encoded by the TIA1

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 ...

. Mutations in the ''TIA1'' gene have been associated with

amyotrophic lateral sclerosis Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease (MND) or—in the United States—Lou Gehrig's disease (LGD), is a rare, Terminal illness, terminal neurodegenerative disease, neurodegenerative disorder that results i ...

frontotemporal dementia Frontotemporal dementia (FTD), also called frontotemporal degeneration disease or frontotemporal neurocognitive disorder, encompasses several types of dementia involving the progressive degeneration of the brain's frontal lobe, frontal and tempor ...

, and Welander distal myopathy. It also plays a crucial role in the development of toxic oligomeric tau in

Alzheimer's disease Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems wit ...

Function

This protein is a member of a RNA-binding protein family that regulates transcription and RNA translation. It was first identified in cytotoxic lymphocyte (CTL) target cells. TIA1 acts in the nucleus to regulate splicing and transcription. TIA1 helps to recruit the splicesome to regulate RNA splicing, and it inhibits transcription of multiple genes, such as the cytokine

Tumor necrosis factor alpha Tumor necrosis factor (TNF), formerly known as TNF-α, is a chemical messenger produced by the immune system that induces inflammation. TNF is produced primarily by activated macrophages, and induces inflammation by binding to its receptors o ...

. In response to stress, TIA1 translocates from the nucleus to the cytoplasm, where it nucleates a type of RNA granule, termed the stress granule, and participates in the translational stress response. As part of the translational stress response, TIA1 works in cooperation with other RNA binding proteins to sequester RNA transcripts away from the ribosome, which allows the cell to focus its protein synthesis/RNA translation machinery on producing proteins that will address the particular stress. It has been suggested that this protein may be involved in the induction of apoptosis as it preferentially recognizes poly(A) homopolymers and induces DNA fragmentation in CTL targets. The major granule-associated species is a 15-kDa protein that is thought to be derived from the carboxyl terminus of the 40-kDa product by proteolytic processing. Alternative splicing resulting in different isoforms of this gene product have been described.

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* {{biochem-stub

Function

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