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The acquisition of wings has facilitated the massive evolutionary success of pterygotes (winged insects), which now make up nearly three-quarters of described metazoans. However, our understanding of how this crucial structure has evolved remains quite elusive. Historically, two ideas have dominated in the wing origin debate, one placing the origin in the dorsal body wall (tergum) and the other in the lateral pleural plates and the branching structures associated with these plates. Through studying wing-related tissues in the wingless segments (such as wing serial homologs) of the beetle, Tribolium castaneum, we obtained several crucial pieces of evidence that support a third idea, the dual origin hypothesis, which proposes that wings evolved from a combination of tergal and pleural tissues. Here, we extended our analysis outside of the beetle lineage and sought to identify wing-related tissues from the wingless segments of the cockroach, Blattella germanica. Through detailed functional and expression analyses for a critical wing gene, vestigial (vg), along with re-evaluating the homeotic transformation of a wingless segment induced by an improved RNA interference protocol, we demonstrate that B. germanica possesses two distinct tissues in their wingless segments, one with tergal and one with pleural nature, that might be evolutionarily related to wings. This outcome appears to parallel the reports from other insects, which may further support a dual origin of insect wings. However, we also identified a vg-independent tissue that contributes to wing formation upon homeotic transformation, as well as vg-dependent tissues that do not appear to participate in wing formation, in B. germanica, indicating a more complex evolutionary history of the tissues that contributed to the emergence of insect wings.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

The plantaris muscle is accessory flexor group muscle of the lower leg. The muscle originates from the lower part of the lateral supracondylar line of the femur and the oblique popliteal ligament, inserted medial to calcaneal tuberosity. During the routine dissection for the undergraduate medical students we encountered accessory plantaris muscle originating medial side of the femoral condyle and capsular ligament. Both the normal lateral and accessory medial tendons fused to form long slender tendon and inserted medial to calcaneal tuberosity. Knowledge of variable origin, course and the insertion of the plantaris muscle is important for surgeons performing various reconstructive surgeries.

В отчете представлены результаты исследований, выполненных по 2 этапу Государственного контракта № П1709 "Молекулярно-генетические основы онтогенетической и генотипической адаптации у Drosophila melanogaster" (шифр "НК-366П") от 23 сентября 2009 по направлению "Физико-химическая молекулярная и клеточная биология" в рамках мероприятия 1.3.2 "Проведение научных исследований целевыми аспирантами", мероприятия 1.3 "Проведение научных исследований молодыми учеными-кандидатами наук и целевыми аспирантами в научно-образовательных центрах", направления 1 "Стимулирование закрепления молодежи в сфере науки, образования и высоких технологий." федеральной целевой программы "Научные и научно-педагогические кадры инновационной России" на 2009-2013 годы. Цель работы - разработка удобных рабочих моделей для анализа явления генотипической и онтогенетической адаптации; В соответствии с основной целью, нами были поставлены следующие задачи: 1 - продолжить длительный направленный отбор на частоту встречаемости повреждения крыла типа «вырезка» в ряду линий дрозофилы, несущих мутацию vestigial в гетерозиготном состоянии; 2 - дополнительно создать ряд линий Drosophila melanogaster для исследования явлений генотипической и онтогенетической адаптации; 3 - применить созданные линии для достижения цели исследования, используя анализ частоты встречаемости повреждения крыла типа «вырезка», комплексный анализ жизнеспособности и анализ морфологической изменчивости крыла на различных стадиях онтогенеза 4 - усовершенствовать следующие методы оценки результатов генетической ассимиляции: а) метод анализа жизнеспособности (общая и индивидуальная плодовитость, частота встречаемости эмбриональных и постэмбриональных леталей); б) метод анализа морфологической изменчивости крыла дрозофилы; 5 - для изучения онтогенетической и генотипической адаптации у Drosophila melanogaster использовать влияние стресса химической природы на примере аминоптерина; 6 - для изучения онтогенетической и генотипической адаптаци

The gene vestigial has been proposed to act as a master gene because of its supposed capacity to initiate and drive wing development. We show that the ectopic expression of vestigial only induces ectopic outgrowths with wing cuticular differentiation and wing blade gene expression patterns in specific developmental and genetic contexts. In the process of transformation, wingless seems to be an essential but insufficient co-factor of vestigial. vestigial ectopic expression alone or vestigial plus wingless co-expression in clones differentiate `mixed' cuticular patterns (they contain wing blade trichomes and chaetae characteristic of the endogenous surrounding tissue) and express wing blade genes only in patches of cells within the clones. In addition, we have found that these clones, in the wing imaginal disc, may cause autonomous as well as non-autonomous cuticular transformations and wing blade gene expression patterns. These non-autonomous effects in surrounding cells result from recruitment or `inductive assimilation' of vestigial or wingless-vestigial overexpressing cells.

This study investigates the role of the homeobox gene Distal-less (Dll) in the development of the legs, antennae, and wings of Drosophila. Lack of Dll function causes a change in the identity of ventral appendage cells (legs and antennae) that often results in the loss of the appendage. Ectopic Dll expression in the proximal region of ventral appendages induces nonautonomous duplication of legs and antennae by the activation of wingless and decapentaplegic. Ectopic Dll expression in dorsal appendages produces transformation into corresponding ventral appendages; wings and halteres develop ectopic legs and the head-eye region develops ectopic antennae. In the wing, the exogenous Dll product induces this transformation by activating the endogenous Dll gene and repressing the wing determinant gene vestigial. It is proposed that Dll induces the development of ventral appendages and also participates in a genetic address that specifies the identity of ventral appendages and discriminates the dorsal versus the ventral appendages in the adult. However, unlike other homeotic genes, Dll expression and function is not defined by a cell lineage border. Dll also performs a secondary and late function required for the normal patterning of the wing.