A genus of fungus gnats belonging to the Sciaridae. Two species, R. angelae and R. hollaenderi, can be reared in the laboratory and have been extensively studied because of the gigantic polytene chromosomes found in various larval tissues (such as the salivary glands, Malpighian tubules, and anterior mid gut). RNA puffs occur often, and they are tissue and developmental stage specific. The DNA puffs are rare and were first discovered in Rhynchosciara. They occur in several regions of the polytene chromosomes of the salivary glands of fourth instar larvae. The DNA in each puff undergoes a 16-fold increase, and the mRNAs transcribed from the amplified genes are translated into salivary proteins. See Classification, Arthropoda, Insecta, Diptera; gene amplification, Sciara.
Subjects: Genetics and Genomics.