Molecular cloning and expression profiling of excitatory amino acid carrier 1 in suckling Huanjiang mini-piglets with large or small body weight at birth Dezhi Fu • Huansheng Yang • Xiangfeng Kong • Francois Blachier • Wence Wang • Yulong Yin Received: 8 June 2012 / Accepted: 18 December 2012 Ó Springer Science+Business Media Dordrecht 2012 Abstract Dietary glutamate is extensively oxidized in enterocytes during its trans-cellular journey from the intes- tinal lumen to the blood. This corresponds to high energy requirement for the absorptive function and renewal of the epithelium. Excitatory amino acid carrier 1 (EAAC1) is known to be the major transporter of glutamate in the intestine. The present study was conducted in Huanjiang mini-piglets which represent a valuable agronomical model for pig production and also extrapolation to human intestinal physiology in order: (i) to determine the amino acid sequence of EAAC1; (ii) to measure the ontogenic expression profiles of jejunal EAAC1 during the suckling period and (iii) to evaluate the influence of low body weight at birth on the expression of EAAC1. For such a purpose, we cloned EAAC1 from Huanjiang mini-pig and used real-time RT- PCR method and Western blotting analysis. Our results show that EAAC1 in the mini-pig encoded a predicted 524-AA protein with eight putative trans-membrane domains. The expression in mRNA and protein of EAAC1 in jejunum was increasing from birth up to 14 days of age and then decreased at 21 days. Piglets with small BW had lower jejunal EAAC1 protein content between birth and after 7 days suckling. These findings indicate that the expression of the EAAC1 in jejunum is much depending on the stage of piglet develop- ment and that low BW at birth is associated with lower expression of this carrier in the early suckling period. Then, it can be hypothesized that lower expression of the intestinal glutamate carrier may decrease the availability of glutamate to enterocytes, thus challenging the optimal absorptive function of the small intestine and normal mucosal growth. Keywords Excitatory amino acid carrier 1  Glutamate  Small body weight  Huanjiang mini-pig, suckling piglet Abbreviations AA Amino acid EAAC1 Excitatory amino acid carrier 1 LBW Large body weight SBW Small body weight IUGR Intrauterine growth retardation Introduction Low birth weight in piglets correlates with lower survival rates, permanent negative growth performance and sub- Dezhi Fu and Huansheng Yang contributed equally to this work. D. Fu  H. Yang  X. Kong (&)  W. Wang  Y. Yin (&) Key Laboratory of Agro-ecological Processes in Subtropical Region, Hunan Provincial Engineering Research Center of Healthy Livestock, Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central, Ministry of Agriculture, Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125, Hunan, China e-mail: nnkxf@isa.ac.cn Y. Yin e-mail: yinyulong@isa.ac.cn D. Fu  H. Yang  W. Wang University of Chinese Academy of Sciences, Chinese Academy of Sciences, Beijing 100049, China X. Kong Huanjiang Observation and Research Station for Karst Ecosystems, Chinese Academy of Sciences, Huanjiang 547100, Guangxi, China F. Blachier UMR 914 Nutrition Physiology and Ingestive Behavior, INRA, CNRH-IdF, AgroParisTech, 16 rue Claude Bernard, 75005 Paris, France 123 Mol Biol Rep DOI 10.1007/s11033-012-2409-y