Differential signalling for enhanced hexose uptake by interleukin (IL)-3 and IL-5 in male germ cells.
We studied the expression and function of the IL (interleukin)-3 and IL-5 family of receptors in male germ cells. RT (reverse transcription)-PCR showed expression of mRNAs encoding the alpha and beta subunits of the IL-3 and IL-5 receptors in human testis, and the presence of IL-3 and IL-5 receptors alpha and beta proteins was confirmed by immunoblotting with anti-alpha and anti-beta antibodies. The immunolocalization studies showed expression of these receptors in the germ line in the human testis and in human and bovine ejaculated spermatozoa. Functional studies with bull spermatozoa indicated that IL-3 signalled for increased uptake of hexoses in these cells at picomolar concentrations compatible with expression of functional high-affinity IL-3 receptors in these cells. In contrast, IL-5 failed to induce increased hexose uptake in bull spermatozoa. Experiments using HL-60 eosinophils that express functional IL-3 and IL-5 receptors confirmed that IL-3, but not IL-5, signalled for increased hexose uptake. Our findings suggest that differential signalling for increased hexose uptake by heteromeric high-affinity IL-3 and IL-5 receptors in mammalian spermatozoa is a property that depends on the identity of the alpha-subunit forming part of the alphabeta-complex and is not a property specific to the germ cells.
Rauch
M Cecilia
MC
Instituto de Bioquímica, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile.
Brito
Mónica
M
Zambrano
Angara
A
Espinoza
Mónica
M
Pérez
Marisol
M
Yañez
Alejandro
A
Rivas
Coralia I
CI
Slebe
Juan Carlos
JC
Vera
Juan Carlos
JC
Concha
Ilona I
II
D000818:Animals; D002417:Cattle; D045744:Cell Line, Tumor; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D005854:Germ Cells / Q000737:chemistry / Q000378:metabolism; D018922:HL-60 Cells / Q000737:chemistry / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D006601:Hexoses / Q000378:metabolism*; D006801:Humans; D007377:Interleukin-3 / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology / Q000502:physiology; D015848:Interleukin-5 / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology / Q000502:physiology; D008297:Male; D021122:Protein Subunits / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D018123:Receptors, Interleukin / Q000235:genetics; D016185:Receptors, Interleukin-3 / Q000235:genetics; D053649:Receptors, Interleukin-5; D012661:Semen / Q000166:cytology; D015398:Signal Transduction / Q000235:genetics*; D013094:Spermatozoa / Q000737:chemistry / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D013737:Testis / Q000737:chemistry / Q000378:metabolism
D006601:Hexoses; D007377:Interleukin-3; D015848:Interleukin-5; D021122:Protein Subunits; D012333:RNA, Messenger; D018123:Receptors, Interleukin; D016185:Receptors, Interleukin-3; D053649:Receptors, Interleukin-5