Sequencing of Hemoglobin Gene 4 (<i>dmhb4</i>) and Southern Blot Analysis Provide Evidence of More Than Four Members of the<i>Daphnia magna</i>Globin Family

Abstract

A genomic fragment containing the hemoglobin gene dmhb4 of Daphnia magna was cloned and its nucleotide sequence determined. Concerning induction under hypoxic conditions, dmhb4 was found to be expressed constitutively with similar mRNA quantities in D. magna bred in either normoxic or hypoxic medium. Southern blot analysis revealed at least six hemoglobin-like sequences in the genome of Daphnia magna.