dc33g10.y1 NICHD_XGC_Emb3 Xenopus laevis cDNA clone IMAGE:3398946 5' similar to gb:M60803 Mouse intronless glutamine synthetase gene, complete (MOUSE); gb:dbj|D50062.1|XELXGS Xenopus laevis mRNA for glutamine synthetase, complete (XENOPUS), mRNA sequence