CXorf66 also known as Chromosome X Open Reading Frame 66, is a 361aa protein in humans that is encoded by the CXorf66 gene. The protein encoded is predicted to be a type 1 transmembrane protein; however, its exact function is currently unknown. CXorf66 has one alias: RP11-35F15.2. There is a patent for CXorf66 under the file US 8586006 by the Institute for Systems Biology and Integrated Diagnostics, Inc. CXorf66 protein is a potential novel cancer biomarker. Gene CXorf66 is located on Chromosome X at Xq27.1 and is on the complement strand. The CXorf66 gene is located between ATP11C ATPase, MIR505, and HNRNPA3P3. In addition to this, according to OMIM, CXorf66 is positioned between SOX3, SPANXB1, and CDR1. mRNA Splice variants CXorf66 only consists of one known splice variant with three exons (1-117, 118-271, and 272-1288bp) and two introns. Locations of junctions occur at 30aa [G] and 81aa [M]. CXorf66 has only been found to have only one polyadenylation site. Protein Composition With 57 serines and 42 lysines, the CXorf66 protein is both serine and lysine rich. CXorf66 has a molecular weight of 39.9kdal and an isoelectric point of 9.89. Domains CXorf66 protein has a predicted signal peptide from 1-19aa, a topological domain from 20-47aa, a transmembrane domain from 48-68aa, and a second topological domain from 69-361aa. A signal peptide cleavage site is predicted to occur between the 17-18aa. Upon analyzing the protein's composition (serine and lysine rich) and post-translational modifications (high levels of phosphorylation), it is predicted that the first topological domain [20-47aa] is extracellular, while the topological domain [69-361aa] is cytoplasmic. A visual can be seen in Figure II. Three repeat motifs of DKPV [31-34 and 204-207aa], SEAK [97-100 and 287-290aa], and PKRS [161-164 and 245-248aa] have been found in the human CXorf66 protein. These repeats are conserved in other primates like Gorilla gorilla gorilla and Macaca mulatta, but are not present in other mammals. SNPs There is one natural variant of the population (frequency 0.436) at 233aa from proline to leucine in the CXorf66 protein, with proline being the ancestral encoded amino acid. No effects have been observed with this missense mutation. Interacting proteins Based on STRING's predicted protein interaction, CXorf66 has medium level scoring for being tied to the proteins listed in Figure III. It is important to note that all proteins listed are not experimentally determined. Regulation Transcription Promoter There is only one known promoter predicted