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Non-AUG translational initiation of a short CAPC transcript generating protein isoform.

ABSTRACT: CAPC (also known as LRRC26) is a new gene with restricted expression in normal tissues, and with expression in many cancers and cancer cell lines. We have identified and characterized a short-transcript of CAPC (S-CAPC). The nucleotide sequence analysis of CAPC mRNA showed that the transcription for S-CAPC starts at position +610 on the L-CAPC transcript. Interestingly, no translation initiation codon 'AUG' is present in this transcript. To determine if a non-AUG start site is utilized, the S-CAPC sequence was cloned into an expression vector with C-terminal myc and histidine tags, and transfected into 293T cells. Western blot and MALDI-TOF MS analysis on purified S-CAPC gave two distinct peaks at approximately 7.5 kDa. N-terminal amino acid sequencing of the purified 7.5 kDa protein product indicated that translation starts at the codon for cysteine on the S

SUBMITTER: Anaganti S

PROVIDER: S-EPMC2664252 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature

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Non-AUG translational initiation of a short CAPC transcript generating protein isoform.

Anaganti Suresh S Hansen Johanna K JK Ha Duc D Hahn Yoonsoo Y Chertov Oleg O Pastan Ira I Bera Tapan K TK

Biochemical and biophysical research communications 20090123 3

CAPC (also known as LRRC26) is a new gene with restricted expression in normal tissues, and with expression in many cancers and cancer cell lines. We have identified and characterized a short-transcript of CAPC (S-CAPC). The nucleotide sequence analysis of CAPC mRNA showed that the transcription for S-CAPC starts at position +610 on the L-CAPC transcript. Interestingly, no translation initiation codon 'AUG' is present in this transcript. To determine if a non-AUG start site is utilized, the S-CA ...[more]

PMID: 19250639

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