Expression of a novel pyridoxal kinase mRNA splice variant, PKH-T, in human testis.
OBJECTIVE
To identify the genes specifically expressed in human adult and fetal testes and spermatozoa.


METHODS
A human testis cDNA microarray was established. Then mRNAs of human adult and fetal testis and spermatozoa were purified and probes were prepared by a reverse transcription reaction with mRNA as the template. The microarray was hybridized with probes of adult and fetal testes and spermatozoa. The nucleic acid sequences of differentially expressed genes were determined and homologies were searched in the databases of GenBank.


RESULTS
A novel human testis-specific gene, PKH-T, was identified by hybridizing adult and fetal testis and spermatozoa probes with a human testis cDNA microarray. The cDNA of PKH-T was 1 069 bp in length. The cDNA sequence of this clone was deposited in the Genbank (AY303972) and PKH-T was also determined as Interim GenSymbol (Unigene, HS.38041). PKH-T contained most PKH conserved motif. The 239 amino acid sequences deduced from the 719 bp open reading frame (ORF) had a homology with the gene PKH (U89606). PKH-T was specifically and strongly expressed in the testis. Comparison of the differential expressions of PKH and PKH-T in testes of different developmental stages indicated that PKH-T was expressed in the adult testis and spermatozoa, while PKH, in the adult, fetal and aged testes. PKH-T had no expression in the testis of Sertoli cell only and partially spermatogenic arrest patients.


CONCLUSIONS
PKH-T is a gene highly expressed in adult human testis and spermatozoa. It may play an important role in spermatogenesis and could be related to male infertility.
Fang
Xing
X
Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing 210029, China.
Zhou
Zuo-Min
ZM
Lu
Li
L
Yin
Lan-Lan
LL
Li
Jian-Min
JM
Zhen
Yin
Y
Wang
Hui
H
Sha
Jia-Hao
JH
D000328:Adult; D000595:Amino Acid Sequence; D018076:DNA, Complementary / Q000096:biosynthesis / Q000235:genetics; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000235:genetics*; D006801:Humans; D007248:Infertility, Male / Q000235:genetics; D007527:Isoenzymes / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D011247:Pregnancy; D011731:Pyridoxal Kinase / Q000096:biosynthesis / Q000235:genetics*; D012326:RNA Splicing / Q000235:genetics*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012708:Sertoli Cells / Q000378:metabolism; D013091:Spermatogenesis / Q000235:genetics; D013094:Spermatozoa / Q000378:metabolism; D013737:Testis / Q000196:embryology / Q000201:enzymology* / Q000254:growth & development; D014018:Tissue Distribution
D018076:DNA, Complementary; D007527:Isoenzymes; D012333:RNA, Messenger; D011731:Pyridoxal Kinase