Polyamines and membrane transporters

Abstract

In recent years, our understanding of the importance of membrane transporters (MTs) in the disposition of and response to drugs has increased significantly. MTs are proteins that regulate the transport of endogenous molecules and xenobiotics across the cell membrane. In mammals, two super-families have been identified: ATP-binding cassette (ABC) and solute carrier (SLC) transporters. There is evidence that MTs might mediate polyamines (PA) transport. PA are ubiquitous polycations which are found in all living cells. In mammalian cells, three major PA are synthesised: putrescine, spermidine and spermine; whilst the decarboxylated arginine (agmatine) is not produced by mammals but is synthesised by plants and bacteria. In addition, research in the PA field suggests that PA are transported into cells via a specific transporter, the polyamine transport system(s) (PTS). Although the PTS has not been fully defined, there is evidence that some of the known MTs might be involved in PA transport. In this mini review, eight SLC transporters will be reviewed and their potential to mediate PA transport in human cells discussed. These transporters are SLC22A1, SLC22A2, SLC22A3, SLC47A1, SLC7A1, SLC3A2, SLC12A8A, and SLC22A16. Preliminary data from our laboratory have revealed that SLC22A1 might be involved in the PA uptake; in addition to one member of ABC superfamily (MDR1 protein) might also mediate the efflux of polyamine like molecules.

Effects of reducing dietary protein on the expression of nutrition sensing genes (amino acid transporters) in weaned piglets

“…The absorption of AA requires many transporter systems that differ with respect to their substrate specificity and driving force (Wang et al, 2009). It has been reported that some genes (such as ASCT2, EAAC1, B 0+ AT, y + LAT1, 4F2hc, and ATB 0 ) that are involved in the control of growth or AA metabolism are regulated by AA availability (Wu, 1998;Lallès et al, 2007;Zhang et al, 2012;Abdulhussein and Wallace, 2014). In our study, we found that, with an increase in the dietary CP level, the expression of AA transporter genes (ASCT2, EAAC1, B 0+ AT, 4F2hc, and ATB 0 ) tended to increase, while an opposite trend was seen related to the abundance of y + LAT1 mRNA.…”

Polyamine Transport Systems in Plants

“…Therefore, PA transport systems have been a subject of interest. Although the major source of PAs is thought to be via de novo biosynthesis, PA uptake and transport are also considered to have signifi cant roles in PA homeostasis (Abdulhussein and Wallace 2014 ;Igarashi and Kashiwagi 2010 ). In plant cells, PAs are localized in cell walls, vacuoles, nuclei, mitochondria, and chloroplasts (Slocum and Flores 1991 ).…”

Breast Milk Polyamines and Microbiota Interactions: Impact of Mode of Delivery and Geographical Location

“…In bacteria, the internal concentration of polyamines is regulated metabolically and through membrane transport [1,23,29] . Several bacteria isolated from human milk have been identified as putrescine producers, which may be a species-level characteristic [30,31] .…”