Abstract
An increasing number of studies suggest that ornithine decarboxylase antizyme 1 (OAZ1), which is regarded as a tumor suppressor gene, regulates follicular development, ovulation, and steroidogenesis. The granulosa cells in the ovary play a critical role in these ovarian functions. However, the action of OAZ1 mediating physiological functions of granulosa cells is obscure. OAZ1 knockdown in granulosa cells of geese was carried out in the current study. The effect of OAZ1 knockdown on polyamine metabolism, cell proliferation, apoptosis, and hormone receptor transcription of primary granulosa cells in geese was measured. The viability of granulosa cells transfected with the shRNA OAZ1 at 48 h was significantly higher than the control (p<0.05). The level of putrescine and spermidine in granulosa cells down-regulating OAZ1 was 7.04- and 2.11- fold higher compared with the control, respectively (p<0.05). The CCND1, SMAD1, and BCL-2 mRNA expression levels in granulosa cells down-regulating OAZ1 were each significantly higher than the control, respectively (p<0.05), whereas the PCNA and CASPASE 3 expression levels were significantly lower than the control (p<0.05). The estradiol concentration, ER and LHR mRNA expression levels were significantly lower in granulosa cells down-regulating OAZ1 compared with the control (p<0.05). Taken together, our results indicated that OAZ1 knockdown elevated the putrescine and spermidine contents and enhanced granulosa cell viability and inhibited ER and LHR transcriptions of granulosa cells in geese.
Highlights
Ornithine decarboxylase antizymes (OAZs) bind to ornithine decarboxylase (ODC), which in turn enhance the degradation of the enzyme protein by the 26S proteasome and inhibit intracellular polyamine influx [1,2,3]
The OAZ2, SAMDC, SPDS, and APAO mRNA expression levels in granulosa cells silencing ornithine decarboxylase antizyme 1 (OAZ1) were significantly higher than the scramble (p
The ODC and SSAT mRNA expression levels in granulosa cells down-regulating OAZ1 were significantly lower than the control (p
Summary
Ornithine decarboxylase antizymes (OAZs) bind to ornithine decarboxylase (ODC), which in turn enhance the degradation of the enzyme protein by the 26S proteasome and inhibit intracellular polyamine influx [1,2,3]. OAZs are considered as negative regulators of intracellular polyamines. The essential role of OAZ1 in inhibiting ODC and polyamine uptake suggests that OAZ1 is a negative regulator of cell proliferation and tumor development [9,10,11]. In addition to accelerate the degradation of ODC, an increasing number of studies indicate that OAZ1 binds to and accelerates the degradation of other proteins shown to regulate cell proliferation, such as AURKA, CCND1, and SMAD1 [16,17,18]
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call