Bovine mammary gene expression profiling during the onset of lactation

摘要

Introduction It is well known that lactogenesis isdefined as the process from the resumption of mammary activity until profuse milk secretion and is divided into two stages (Barry,1970).Stage Ⅰ is the period from the resumption of mammary activity to the time of parturition.Stage Ⅱ is initiated around the time of parturition and extends for several days aflerwards.Kiera compared the transcriptomes of pre-and post-parturition mammary glands of dairy cows using Affymetrix GeneChip Bovine Genome Array,and provided only some insights into the molecular events of stage Ⅱ (Finucane et al.,2008).Lemay analyzed the microarray data sets of mammary gland RNA samples collected from FVB mice at 10 time points during mammary development,and suggested that there was no sudden transcriptional switch around the time of parturition (Lemay et al.,2007).With the recently developed RNA deep sequencing technology,such as Digital gene expression (DGE),and genome backgrounds of bovine available,it is not a challenging task to understand the molecular events underlying the lactogenesis.