Details

Autor(en) / Beteiligte

• Sadek, Christine M.
• Damdimopoulos, Anastasios E.
• Pelto‐Huikko, Markku
• Gustafsson, Jan‐Åke
• Spyrou, Giannis
• Miranda‐Vizuete, Antonio

Titel

Sptrx‐2, a fusion protein composed of one thioredoxin and three tandemly repeated NDP‐kinase domains is expressed in human testis germ cells

Ist Teil von

• Genes to cells : devoted to molecular & cellular mechanisms, 2001-12, Vol.6 (12), p.1077-1090

Ort / Verlag

Oxford, UK: Blackwell Science Ltd

Erscheinungsjahr

2001

Link zum Volltext

Quelle

Free E-Journal (出版社公開部分のみ）

Beschreibungen/Notizen

• Background Thioredoxins (Trx) are small redox proteins that function as general protein disulphide reductases and regulate several cellular processes such as transcription factor DNA binding activity, apoptosis and DNA synthesis. In mammalian organisms, thioredoxins are generally ubiquitously expressed in all tissues, with the exception of Sptrx‐1 which is specifically expressed in sperm cells. Results We report here the identification and characterization of a novel member of the thioredoxin family, the second with a tissue‐specific distribution in human sperm, termed Sptrx‐2. The Sptrx‐2 ORF (open reading frame) encodes for a protein of 588 amino acids with two different domains: an N‐terminal thioredoxin domain encompassing the first 105 residues and a C‐terminal domain composed of three repeats of a NDP kinase domain. The Sptrx‐2 gene spans about 51 kb organized in 17 exons and maps at locus 7p13‐14. Sptrx‐2 mRNA is exclusively expressed in human testis, mainly in primary spermatocytes, while Sptrx‐2 protein expression is detected from the pachytene spermatocytes stage onwards, peaking at round spermatids stage. Recombinant full‐length Sptrx‐2 expressed in bacteria displayed neither thioredoxin nor NDP kinase enzymatic activity. Conclusions The sperm specific expression of Sptrx‐2, together with its chromosomal assignment to a position reported as a potential locus for flagellar anomalies and male infertility phenotypes such as primary ciliary dyskinesia, suggests that it might be a novel component of the human sperm axonemal organization.