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Updated: Jun 21, 2026
08:19
Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
Developmental switch of CREM function during spermatogenesis: from antagonist to activator
N S Foulkes1, B Mellström, E Benusiglio
1Laboratoire de Génétique Moléculaire des Eucaryotes du CNRS, Strasbourg, France.
Nature
|January 2, 1992
Summary
Researchers discovered a new form of the CREM gene, called CREM tau, in adult testes. This isoform switches from inhibiting to activating gene expression during sperm development, crucial for male fertility.
Area of Science:
- Reproductive biology
- Molecular genetics
- Cell signaling
Background:
- Spermatogenesis is regulated by the pituitary-hypothalamic axis and adenylate cyclase signaling.
- The CREM gene produces alternative splicing variants that modulate cAMP transcriptional responses.
Purpose of the Study:
- To identify and characterize novel CREM isoforms in adult mammalian testes.
- To investigate the functional role of CREM isoforms during spermatogenesis.
Main Methods:
- Analysis of gene expression and splicing patterns in testicular cells.
- Characterization of protein domains and transcriptional activity of novel CREM isoforms.
Main Results:
- A novel CREM isoform, CREM tau, was identified in adult testis.
- CREM tau possesses two glutamine-rich domains, conferring transcriptional activation.
- CREM expression switches from an antagonist form in premeiotic cells to an activator form (CREM tau) from the pachytene stage onwards.
Conclusions:
- The discovery of CREM tau highlights its critical role in regulating gene expression during spermatogenesis.
- Splicing-dependent functional reversal of CREM is a key mechanism for developmental modulation in gene expression during male germ cell development.
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