Analysis of maize brittle-1 alleles and a defective Suppressor-mutator-induced mutable allele.

AUTOR(ES)

Sullivan, T D

RESUMO

A mutant allele of the maize brittle-1 (bt1) locus, brittle-1-mutable (bt1-m), was shown genetically and molecularly to result from the insertion of a defective Suppressor-mutator (dSpm) transposable element. An Spm-hybridizing restriction enzyme fragment, which cosegregates with the bt1-m allele and is absent from wild-type revertants of bt1-m, was identified and cloned. Non-Spm portions of it were used as probes to identify wild-type (Bt1) cDNAs in an endosperm library. The 4.3-kb bt1-m genomic clone contains a 3.3-kb dSpm, which is inserted in an exon and is composed of Spm termini flanking non-Spm sequences. RNA gel blot analyses, using a cloned Bt1 cDNA probe, indicated that Bt1 mRNA is present in the endosperm of developing kernels and is absent from embryo or leaf tissues. Several transcripts are produced by bt1-m. The deduced translation product from a 1.7-kb Bt1 cDNA clone has an apparent plastid transit peptide at its amino terminus and sequence similarity to several mitochondrial inner-envelope translocator proteins, suggesting a possible role in amyloplast membrane transport.

Documentos Relacionados

• Alternative 3' splice acceptor sites modulate enzymic activity in derivative alleles of the maize bronze1-mutable 13 allele.
• Mutable R-Navajo Alleles of Cyclic Origin in Maize
• Molecular Analysis of Multiple Mutator-Derived Alleles of the Bronze Locus of Maize
• Characterization of an Spm-Controlled Bronze-Mutable Allele in Maize
• Crossing over in Heterozygotes Carrying Different Mutable Alleles at the A1 Locus in Maize