O gene TCP5 se expressa em tecidos vegetativos, como folhas, mas também em tecidos florais, preferencialmente na região apical do meristema floral e dos primórdios dos órgãos florais. Este mesmo padrão de expressão foi observado em outros estudos com TCPs de classe II, e possivelmente reflete o papel destes genes na regulação negativa da divisão celular e consequente entrada no processo de diferenciação/expansão celular, já que os órgãos de plantas maturam no sentido distal-proximal.
A comparação de plantas transgênicas superexpressando TCP5 na epiderme (construção pATML1:TCP5) ou com níveis reduzidos de TCP5 (35S:miR-3TCP e mutante
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simples tcp5) revelaram possíveis papéis biológicos para TCP5 no desenvolvimento dos órgãos florais. A supressão de TCP5, juntamente com TCP13 e TCP17, causou aumento nos tamanhos dos órgãos florais. Este aumento no tamanho pode ser devido a uma maior taxa de proliferação celular nestas plantas, como observado em pétalas neste estudo. A superexpressão de TCP5 na epiderme modificou a forma e o tamanho das pétalas, e a forma dos pistilos. As pétalas são mais compridas do que as do tipo selvagem, o que pode ser resultado de uma maior expansão das células que as compõem, uma vez que as células da epiderme adaxial são maiores. Observou-se ainda más-formações nos pistilos e germinação ectópica de grãos de pólen, o que pode afetar a fertilidade destas plantas. Juntos, os resultados corroboram a hipótese de que o gene TCP5 atua no desenvolvimento de órgãos florais da mesma maneira que outros CIN-TCPs: regulando negativamente a proliferação celular e aumentando a expansão celular.
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