In the Silkworm NBRP at Kyushu University, about 750 strains are maintained, and distributed to many researchers.
Among them, p50T was utilized for whole genome sequencing, and its accurate genome assembly was published in
2008. Nevertheless, the genomes of other strains have not yet been sequenced. In the same program, last year (2015),
we selected 18 Bombyx mori strains and 2 B. mandarina ones, analyzed their genomes by an Illumina sequencer, and
released the resultant sequences in DDBJ and GenBank. This year (2016), we will perform highly accurate sequencing
of the genome of a Japanese, inbred strain (Sakado) of B. mandarina by using a single molecule realtime sequencer
(PacBio). B. mandarina is the ancestral species of B. mori, and exhibits “wild” phenotypes including mimicry in
larvae and flight ability in adults, which have been lost in B. mori during domestication. On the other hand,
B. mandarina produces smaller cocoons thanB. mori.
Although B. mori and B. mandarina can be interspecifically
hybridized and produce their fertile progenies, their karyotypes are different; n = 28 in
B. mori and n = 27 in B. mandarina. Therefore,
B. mandarina is a valuable resource for comparative genomics in both phenotypic and cytological
points of view, and its genomic information will be useful for researchers.