Where is the Neurofibromin gene located?

Where is the Neurofibromin gene located?

Neurofibromin 1 (NF1) is a gene in humans that is located on chromosome 17.

Is the gene for Neurofibromin heterozygous or homozygous?

CLINICAL DESCRIPTION AND DIAGNOSIS Neurofibromatosis 1 (NF1) is an autosomal dominant condition caused by heterozygous mutations of the NF1 gene.

How does neurofibromatosis affect DNA?

NF is considered an autosomal dominant disorder because the gene is located on one of the 22 chromosome pairs, called autosomes. The gene for NF1 is located on chromosome 17. The gene for NF2 is located on chromosome 22. Children have a 50 percent chance of inheriting the genes that cause NF if the parent has NF.

How long is Neurofibromin gene?

NF1 is a large gene that spans 350 kb of genomic DNA sequence [1]. Its transcript is 11 to 13 kb long, with an 8454-bp open reading frame [11] and 3.5 kb of 3′ untranslated region [12]. It contains 60 exons and is ubiquitously expressed [2] (Figure 1).

What is the function of Neurofibromin?

Neurofibromin acts as a tumor suppressor protein. Tumor suppressors normally prevent cells from growing and dividing too rapidly or in an uncontrolled way. This protein appears to prevent cell overgrowth by turning off another protein (called ras) that stimulates cell growth and division.

How is Neurofibromin produced?

Neurofibromatosis is caused by genetic defects (mutations) that either are passed on by a parent or occur spontaneously at conception. The specific genes involved depend on the type of neurofibromatosis: NF1 . The NF1 gene is located on chromosome 17.

How does NF1 change Neurofibromin gene and the Neurofibromin protein?

Neurofibromatosis type 1 This shortened protein cannot perform its normal job of inhibiting cell division. When mutations occur in both copies of the NF1 gene in Schwann cells, the resulting loss of neurofibromin allows noncancerous tumors called neurofibromas to form.

What type of inheritance is neurofibromatosis?

Neurofibromatosis type 1 is considered to have an autosomal dominant pattern of inheritance. People with this condition are born with one mutated copy of the NF1 gene in each cell. In about half of cases, the altered gene is inherited from an affected parent .

What gene is associated with neurofibromatosis?

The NF1 gene is located on chromosome 17. This gene produces a protein called neurofibromin that helps regulate cell growth. The mutated gene causes a loss of neurofibromin, which allows cells to grow uncontrolled. NF2 .

What type of gene mutation is neurofibromatosis?

What is axillary freckling?

Definition. The presence in the axillary region (armpit) of an increased number of freckles, small circular spots on the skin that are darker than the surrounding skin because of deposits of melanin. [

What is the function of neurofibromin?

This protein is produced in many types of cells, including nerve cells and specialized cells called oligodendrocytes and Schwann cells that surround nerves. These specialized cells form myelin sheaths, which are the fatty coverings that insulate and protect certain nerve cells. Neurofibromin acts as a tumor suppressor protein.

What does the NF1 gene do?

The NF1 gene encodes a protein referred to as “neurofibromin,” which is a GTPase activating protein (GAP) that stimulates conversion of Ras-GTP to Ras-GDP. As such, it is involved in control of the response of cells to growth stimuli.

Is neutneurofibromin a Ras-GTPase activating protein?

Neurofibromin, the protein product of NF1, is a Ras-GTPase-activating protein (Ras-GAP) and is known to inhibit Ras–mTOR signaling in astrocytes ( Scheffzek et al., 1998 ).

How does neoneurofibromin affect the intracellular signal transduction protein RAS?

Neurofibromin functions as a GAP protein and inactivates the intracellular signal transduction protein Ras by converting the active GTP-bound form into its inactive GDP-bound form. This in turn leads to the downregulation of Ras activity. Loss of neurofibromin activity increases Ras activity,…