Transcripts levels of PenB_CYSP , PenB_MT2 and PenB_MT3 genes are connected to with archegonia development. Quantitative real-time PCR analyses of three studied genes show different transcripts levels in the vegetative and archegonia bearing parts of female gametophytes grown in natural habitat. All transcript levels were normalized against ACTIN1. As a control of comparable gene expression in the tested female thalli primers amplifying fragment of histone H4 were used. Calculation shows the mean ± SD from three technical replicates.