Molecular cloning of two classes of Em-like proteins from the seeds of the leguminous tree Robinia pseudoacacia

To check for the presence of Em-like proteins in seeds of the leguminous tree Robinia pseudoacacia L. (black locust), a cDNA library constructed from mRNA isolated from developing seeds was screened using radiolabeled cDNA encoding the Em protein from Vigna radiata as a probe. Sequence analysis of the identified cDNA clones revealed two classes of Em proteins in Robinia. The nucleotide sequence data for each class have been submitted to Genbank/EMBL Data library and are available under the accession numbers U40820 and U40821. Northern blot analysis demonstrated that the Robinia Em proteins are translated from mRNAs of approximately 800 nucleotides, which are abundant in the seed but are not expressed in the bark. Southern blot analysis indicated that the Em proteins in Robinia are encoded by at least two genes. The Robinia Em proteins have a high degree of sequence homology with previously characterized Em-like proteins from both monocots and dicots.