Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^tin.CΔ4 results in enlargement of the end-diastolic dimension of the adult heart, but does not cause a significant change in fractional shortening.

Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^P0.5.Pdf affects adult locomotor activity rhythms; 57.8% of the flies have a single rhythm, 26.9% of flies have a complex rhythm (classified as more than one rhythmic period detectable above the 95% significance line using Lomb-Scargle analysis of periodograms) and 7.7% are arrhythmic.

Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^tim.Scer\UAS affects adult locomotor activity rhythms; 12.1% of the flies have a single rhythm, 6.1% of flies have a complex rhythm (classified as more than one rhythmic period detectable above the 95% significance line using Lomb-Scargle analysis of periodograms) and 81.8% are arrhythmic.

Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^en-e16E affects the patterning of the epidermis and disrupts dorsal closure in the embryo.

Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^ey.PH results in a headless phenotype. Three classes of phenotype are seen; class I pharate adults lack all head structures derived from the eye-antennal discs, class II consists of eyeless flies which lack most head structures and both antennae and class III consists of eyeless animals with large parts of the head missing but one or both antennae present.

Embryos expressing Mef2^Scer\UAS.cBa under the control of Scer\GAL4^da.G32 fail to retract. Epidermal differentiation is impaired, as although a cuticle is secreted, it is extremely thin and lacks denticles. Expression of Mef2^Scer\UAS.cBa under the control of Scer\GAL4^twi.PB results in abnormalities in the somatic musculature, heart and midgut. The alary muscles and the pharyngeal muscle are unaffected. Two effects are seen on the somatic musculature; firstly, a number of round, unfused myosin-expressing cells (whose size, shape and position suggests that they are unfused myoblasts) are seen around the muscles. Secondly, the stereotyped pattern of muscles in each abdominal hemisegment is disrupted. Deletions and duplications of muscles, as well as muscles found in the wrong position and muscles with abnormal shapes are seen. The precise defects vary from segment to segment and from embryo to embryo. The heart is somewhat shorter than normal in the anterior/posterior axis, and there are one or two additional rows of myosin-expressing cells posteriorly. The number of cardioblasts is significantly less than in wild-type embryos. The pericardial cells are also disorganised in the posterior region of the heart. The midgut fails to constrict and has a bloated appearance.

Embryos in which Mef2^Scer\UAS.cBa is expressed using Scer\GAL4^69B do not hatch and die as late embryos which show no trachea formation and no body-wall movement. These embryos also fail to undergo dorsal closure, resulting in a large opening on the dorsal side, through which the gut is extruded. Embryos in which Mef2^Scer\UAS.cBa is expressed using Scer\GAL4^hs.2sev together with heat shock have a similar phenotype; they die during late embryogenesis, do not show tracheal formation, show no body-wall movement, and have defects in dorsal closure resulting in a large opening on the dorsal side. Embryos in which Mef2^Scer\UAS.cBa is expressed using Scer\GAL4¹⁴⁰⁷ die as late embryos, although they have normal trachea and muscle morphology and show slow body-wall movement. They also show incomplete dorsal closure, resulting in a small opening on the dorsal side. There are no gross defects in the central and peripheral nervous systems. Embryos in which Mef2^Scer\UAS.cBa is expressed using Scer\GAL4^how-24B die as late embryos. They show some body-wall movement, although the pattern of body-wall muscles is abnormal and several unfused myoblasts are seen. This phenotype is enhanced if the embryos are raised at 29^oC.

Expression in Mef2^22-21/Df(2R)520 embryos allows significant muscle fibre formation in the correct location and with correct attachments. None of the embryos survive to larvae.

Mef2^UAS.cBa, Scer\GAL4^ey.PH has visible phenotype, suppressible | partially by CycE^UAS.cLa, Scer\GAL4^ey.PH

Mef2^UAS.cBa, Scer\GAL4^ey.PH has visible phenotype, suppressible | partially by Myc^UAS.cZa, Scer\GAL4^ey.PH

Mef2^UAS.cBa, Scer\GAL4^ey.PH has adult head phenotype, suppressible | partially by CycE^UAS.cLa, Scer\GAL4^ey.PH

Mef2^UAS.cBa, Scer\GAL4^ey.PH has adult head phenotype, suppressible | partially by Myc^UAS.cZa, Scer\GAL4^ey.PH

Mef2^UAS.cBa, Scer\GAL4^Mef2.PR is a suppressor | partially of embryonic/larval somatic muscle cell phenotype of Scer\GAL4^Mef2.PR, mir-92b^UAS.cCa

Mef2^UAS.cBa, Scer\GAL4^twi.PB is a suppressor | partially of embryonic/larval muscle system phenotype of Him^UAS.cLa, Scer\GAL4^twi.PB