Molecular cloning, genomic organization, and expression of a testicular isoform of hormone-sensitive lipase

Journal Article · Thu Aug 01 04:00:00 EDT 1996 · Genomics

DOI:https://doi.org/10.1006/geno.1996.0383· OSTI ID:465978

Holst, L S; Laurell, H; Holm, C ^[1]

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1. Lund Univ. (Sweden); and others

By catalyzing the rate-limiting step in adipose tissue lipolysis, hormone-sensitive lipase (HSL) is an important regulator of energy homeostasis. The role and importance of HSL in tissues other than adipose are poorly understood. We report here the cloning and expression of a testicular isoform, designated HSL{sub tes}. Due to an addition of amino acids at the NH{sub 2}-termini, rat and human HSL{sub tes} consist of 1068 and 1076 amino acids, respectively, compared to the 768 and 775 amino acids, respectively, of the adipocyte isoform (HSL{sub adi}). A novel exon of 1.2 kb, encoding the human testis-specific amino acids, was isolated and mapped to the HSL gene, 16 kb upstream of the exons encoding HSL{sub adi}. The transcribed mRNA of 3.9 kb was specifically expressed in testis. No significant similarity with other known proteins was found for the testis-specific sequence. The amino acid composition differs from the HSL{sub adi} sequence, with a notable hydrophilic character and a high content of prolines and glutamines. COS cells, transfected by the 3.9-kb human testis cDNA, expressed a protein of the expected molecular mass (M{sub r} {approximately}120,000) that exhibited catalytic activity similar to that of HSL{sub adi}. Immunocytochemistry localized HSL to elongating spermatids and spermatozoa; HSL was not detected in interstitial cells. 34 refs., 5 figs.

• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 465978
• Journal Information: Genomics, Journal Name: Genomics Journal Issue: 3 Vol. 35; ISSN 0888-7543; ISSN GNMCEP
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
ADIPOSE TISSUE
AMINO ACIDS
DNA SEQUENCING
DNA-CLONING
ENERGY
GENE AMPLIFICATION
GENE REGULATION
GENETIC MAPPING
GLUTAMINE
HOMEOSTASIS
HORMONES
HUMAN CHROMOSOME 19
LIPASES
PROLINE
SPERMATOZOA
STRUCTURE-ACTIVITY RELATIONSHIPS
TESTES
TISSUE DISTRIBUTION
TRANSCRIPTION