HPV infection in semen: results from a new molecular approach.

Human papillomavirus (HPV) is the agent of the most common sexually transmitted diseases causing a variety of clinical manifestations ranging from warts to cancer. Oncogenic HPV infection is the major cause of cervical cancer and less frequently of penile cancers. Its presence in semen is widely known, but the effects on fertility are still controversial. We developed a new approach to evaluate virus localisation in the different semen components. We analysed also the specific genotype localisation and viral DNA quantity by qPCR. Results show that HPV DNA can be identified in every fraction of semen: spermatozoa, somatic cells and seminal plasma. Different samples can contain the HPV DNA in different fractions and several HPV genotypes can be found in the same fraction. Additionally, different fractions may contain multiple HPV genotypes in different relative quantity. We analysed the wholeness of HPV DNA in sperm cells by qPCR. In one sample more than half of viral genomes were defective, suggesting a possible recombination event. The new method allows to easily distinguish different sperm infections and to observe the possible effects on semen. The data support the proposed role of HPV in decreased fertility and prompt new possible consequences of the infection in semen.

Isolation and characterization of a Paracentrotus lividus cDNA encoding a stress-inducible chaperonin.

Chaperonins are ubiquitous proteins that facilitate protein folding in an adenosine triphosphate-dependent manner. Here we report the isolation of a sea urchin cDNA (Plhsp60) coding for mitochondrial chaperonin (Cpn60), whose basal expression is further enhanced by heat shock. The described cDNA corresponds to a full-length mRNA encoding a protein of 582 amino acids, the first 32 of which constitute a putative mitochondrial targeting leader sequence. Comparative analysis has demonstrated that this protein is highly conserved in evolution.

Sea urchin neural alpha2 tubulin gene: isolation and promoter analysis.

Expression of Talpha2 gene, during sea urchin Paracentrotus lividus development, is spatially and temporally regulated. In order to characterize this gene, we isolated the relevant genomic sequences and scanned the isolated 5'-flanking region in searching for cis-regulatory elements required for proper expression. Gel mobility shift and footprinting assays, as well as reporter gene (CAT and beta-gal) expression assays, were used to address cis-regulatory elements involved in regulation. Here we report that an upstream 5'-flanking fragment of PlTalpha2 gene drives temporal expression of reporter genes congruent with that of endogenous Talpha2 gene. The fragment contains cis-elements able to bind nuclear proteins from the gastrula stage (at which the Talpha2 gene is expressed) whose sequences could be consistent with the consensus sequences for transcription factors present in data bank.