Core Facilities, Centre for Genomic Regulation, UPF, Barcelona, Spain. manuela.hummel@crg.es|Core Facilities, Centre for Genomic Regulation, UPF, Barcelona, Spain. manuela.hummel@crg.es|Core Facilities, Centre for Genomic Regulation, UPF, Barcelona, Spain. manuela.hummel@crg.es|Core Facilities, Centre for Genomic Regulation, UPF, Barcelona, Spain. manuela.hummel@crg.es