High impact information on Asb4

• One complementary deoxyribonucleic acid clone of a low-molecular-weight mRNA (asb4/134) is specific to the distal small bowel, specifically accumulates at weaning, and hybridizes to RNA from mouse testis and brain at approximately 2%-5% of the intestinal level [1].
• Recently, two imprinted genes, paternally expressed Sgce and maternally expressed Asb4, were identified in this region [2].
• Based on its differential expression, neuroanatomical distribution and colocalisation, we hypothesise that Asb-4 is a gene involved in energy homeostasis [3].
• Reverse transcription quantitative polymerase chain reaction was used to validate down-regulation of Asb-4 mRNA in the arcuate nucleus of the fasted Sprague-Dawley rat (relative expression of Asb-4 mRNA: fed = 4.66 +/- 0.26; fasted = 3.96 +/- 0.23; n = 4, P < 0.01) [3].
• Down-regulation was also demonstrated in the obese fa/fa Zucker rat, another model of energy disequilibrium (relative expression of Asb-4 mRNA: lean Zucker = 3.91 +/- 0.32; fa/fa = 2.93 +/- 0.26; n = 5, P < 0.001) [3].

Biological context of Asb4

• One of the down-regulated mRNAs was ankyrin-repeat and suppressor of cytokine signalling box-containing protein 4 (Asb-4) [3].

Anatomical context of Asb4

• In situ hybridisation shows that Asb-4 mRNA is expressed in brain areas linked to energy homeostasis, including the arcuate nucleus, paraventricular nucleus, dorsomedial nucleus, lateral hypothalamus and posterodorsal medial amygdaloid area [3].

References