Requests for the pHyg3 plasmid or questions concerning this transformation system should be directed to: To introduce the HgyR marker into Chlamydomonas cells we are using the glass bead method of Karen Kindle. Both pHyg3 and pHyg4 have been used to transform both cell wall deficient (cw2, cw15) and wild type (CC124) strains, pHyg4 being somewhat less efficient in terms of transformation rates (probably due to the lack of an intron). Transformants can be selected easily on TAP plates supplemented with 10 µg hygromycinB per ml. We buy ‘our’ hygromycinB from Roche (order no. 843 555). Details of the construction and transformation protocols can be found in our pertinent publication (see above). You can also get some additional information that may be useful following this link: Please note: The labeling of the rbcS2 intron in our respective publication (Berthold et al. 2002. Protist, Vol. 153, 401–412) is wrong. Four bases (418-421) in the following figure which is taken from our publication in fact do belong to the rbcS2 intron. The box for the intron was inadvertently misplaced in the published figure (using the wrong GT as the intron 5′ border). Source.