Molecular characterization and nutritional regulation of specificity protein 1 (Sp1) in grass carp (Ctenopharyngodon idella )

Abstract

Specificity protein 1 (Sp1) is a ubiquitous nuclear factor in eukaryotic cells and plays a crucial role in the regulation of di-/tripeptide absorption in the intestine. However, the function of Sp1 in bony fish remains poorly understood. In this study, a fish Sp1 gene (designated CiSp1) was identified from Ctenopharyngodon idella. The deduced CiSp1 protein contains structural features typical of Sp1 family proteins, including a glutamine-rich (Q-rich) region and three typical Cys2His2 zinc fingers. Quantitative real-time PCR analysis revealed ubiquitous expression of CiSp1 in all tested tissues and embryonic developmental stages of grass carp. In addition, CiSp1 expression in the intestine was significantly increased after feeding with fish meal and 270 g/kg dietary protein. Moreover, in vitro and in vivo glutamine dipeptide treatments showed similar stimulatory effects on the expression of the transcription factors CiSp1 and CiCDX2 and their potential target gene CiPepT1 in the intestines of grass carp. Finally, our results demonstrated that the mRNA expression of CiSp1/CiCDX2/CiPepT1 in the intestine was significantly increased after treatment with sodium butyrate in vitro and in vivo. Altogether, these results demonstrate for the first time that grass carp possesses a functional Sp1 and that its expression is regulated by dietary protein and feed additives. K E Y W O R D S characterization, Ctenopharyngodon idella, expression profile, nutritional regulation, specificity protein 1

Effects of dietary glutamine supplementation on growth performance, antioxidant status and intestinal function in juvenile grass carp (Ctenopharyngodon idella)

“…However, no detailed information exists regarding the effects of dietary Gln supplementation on protein absorption factors in bony fish. In the present study, we analysed six key factors, including APN, CDX2, LAT2, PEPT1, SP1 and SP3, that play crucial roles in both protein absorption and intestinal development in grass carp (Liu, Zhou, Feng et al, ; Liu, Zhou, Zhou et al, ; Qu et al, ; Tang et al, ). The functions of these protein absorption factors have been well demonstrated (Clark, Macdonald, & Stark, ; Genciana et al, ; Shimakura, Terada, Shimada, Katsura, & Inui, ; White, Mulligan, King, & Sanderson, ; Yang, Tan, Zhu, & Chen, ).…”

Effects of dietary soy isoflavones on growth, antioxidant status, immune response and resistance of juvenile grass carp ( Ctenopharyngodon idella ) to Aeromonas hydrophila challenge

“…β-Actin was used as the internal reference for normalization. The PCR primers of IFN-γ2, TNF-α and IL-6 were referred to the previous paper (Tian et al, 2017) Real-time PCR analysis was conducted according to previous work by our laboratory (Qu et al, 2018). Briefly, the total RNA in two tissues of experimental fish before and after challenge test was extracted using an RNAiso plus kit (TaKaRa) according to the instruction of manufacturer.…”

SP1 Promotes HDAC4 Expression and Inhibits HMGB1 Expression to Reduce Intestinal Barrier Dysfunction, Oxidative Stress, and Inflammatory Response after Sepsis

“…As known, sepsis could lead to the mutations of the symbiotic intestinal microenvironment, causing a dysbiotic environment, which further promote the hyperinflammation, hyperpermeability, and apoptosis of epithelial cells, and domination of pathogenic bacteria [ 26 ]. SP1, a ubiquitous nuclear factor in eukaryotic cells, may play essential roles in the regulation of di-/tripeptide absorption in the intestine [ 27 ]. Furthermore, it has been indicated that SP1 can increase the claudin-1 transcription to enhance intestinal barrier function, which is essential for the maintenance of normal intestinal function [ 28 ].…”