Analysis of the ribosomal RNA gene repeat from the moss Funaria hygrometrica

Ribosomal DNA from the moss Funaria hygrometrica was obtained by centrifugation of genomic DNA in a Hoechst 33258-CsCl density gradient. One of the three DNA-satellite bands (GC2) represented the ribosomal fraction. After digestion with EcoRI three larger fragments were obtained which hybridized to the large and small ribosomal subunits from Sinapis alba. The fragments were cloned and sequenced. The complete ribosomal DNA consists of 11,132 bp. The analysis of the 18S, 5.8S and 25S rDNA revealed a high sequence and length similarity to other plant sequences. An intron of 169 bp situated 10 bp from the 5' end of the 25 S rDNA was found. The intergenic spacer (IGS) has a length of 5150 bp with 13 highly conserved subrepeats (38 bp except for two of 56 bp) followed directly by 6 other repeated elements of 42-43 bp. Two putative transcription initiation sites (TIS) were identified with some differences to known TIS of angiosperms.